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-rw-r--r--emu-radio/common-library/communication-protocol.cc349
-rw-r--r--emu-radio/common-library/communication-protocol.h68
-rw-r--r--emu-radio/common-library/connection-pool.cc58
-rw-r--r--emu-radio/common-library/connection-pool.h48
-rw-r--r--emu-radio/common-library/emulator.h52
-rw-r--r--emu-radio/common-library/json.h10794
-rw-r--r--emu-radio/common-library/query.cc219
-rw-r--r--emu-radio/common-library/query.h92
-rw-r--r--emu-radio/common-library/tcp-server.cc146
-rw-r--r--emu-radio/common-library/tcp-server.h55
-rw-r--r--emu-radio/common-library/websocket-server.cc105
-rw-r--r--emu-radio/common-library/websocket-server.h53
12 files changed, 12039 insertions, 0 deletions
diff --git a/emu-radio/common-library/communication-protocol.cc b/emu-radio/common-library/communication-protocol.cc
new file mode 100644
index 00000000..905ef44c
--- /dev/null
+++ b/emu-radio/common-library/communication-protocol.cc
@@ -0,0 +1,349 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "communication-protocol.h"
+
+
+///////////////////
+//Explanation: A query can select/update 2 objects:
+// - Coordinates of a node
+// - MCS value
+//
+// AllowedObjectName select the generic object to update/select. Not all the action are allowed on a generic object.
+// Furthermore not al the parameters of an object can be selected/updated.
+// So an object has a list of attributes that is possible to update/select. Also There are filter: a node can be updated just if
+// matches a certain filter. A filter is a tuple [key operand value]. Not all the operand are allowed on a key.
+//////////////////
+
+// TODO To improve. Right now just basic controls and actions
+
+std::set<std::string> ProtocolDetails::AllowedObjectName = {"interface"};
+std::set<std::string> ProtocolDetails::AllowedActions = {"update", "select", "subscribe"};
+std::set<std::string> ProtocolDetails::AllowedFields = {"id", "x", "y", "rate"};
+std::set<std::string> ProtocolDetails::AllowedFilters = {"id"};
+std::set<std::string> ProtocolDetails::AllowedOperands = {"=="};
+//std::map<std::string, std::set<std::string>> ProtocolDetails::AllowedParameters = {
+// {"node", {"x", "y", "physical-rate"}},
+//};
+
+// {"x", {"<", "<=", "==", ">", ">=", "!="}},
+// {"y", {"<", "<=", "==", ">", ">=", "!="}},
+// {"MCS", {"<", "<=", "==", ">", ">=", "!="}}
+
+CommunicationProtocol::CommunicationProtocol (ProtocolVersion version)
+ : version (version)
+{
+}
+
+bool CommunicationProtocol::checkFields (const std::string &field)
+{
+ if (ProtocolDetails::AllowedFields.find (field) == ProtocolDetails::AllowedFields.end ())
+ {
+ return false;
+ }
+
+ return true;
+}
+
+bool CommunicationProtocol::checkAction (const std::string &action)
+{
+ if (ProtocolDetails::AllowedActions.find (action) != ProtocolDetails::AllowedActions.end ())
+ {
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+}
+
+bool CommunicationProtocol::checkObjectName (const std::string &objectName)
+{
+ if (ProtocolDetails::AllowedObjectName.find (objectName) != ProtocolDetails::AllowedObjectName.end ())
+ {
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+}
+
+bool CommunicationProtocol::checkFilter (const std::vector<std::string> &filter)
+{
+ // TODO So far just the filter interface id == something is supported.
+
+ if (filter.size () < 3)
+ {
+ std::cerr << "The format of the filter is not correct." << std::endl;
+ return false;
+ }
+
+ if (ProtocolDetails::AllowedFilters.find (filter[0]) != ProtocolDetails::AllowedFilters.end ())
+ {
+ // The filter is supported
+ if (filter[0] == "id")
+ {
+ if (ProtocolDetails::AllowedOperands.find (filter[1]) == ProtocolDetails::AllowedOperands.end ())
+ {
+ std::cerr << "The operand expressed in the filter is not compatible with the key of the filter"
+ << std::endl;
+ return false;
+ }
+ }
+ }
+ else
+ {
+ std::cerr << "The filter contains an unknown key." << std::endl;
+ return false;
+ }
+
+ return true;
+}
+
+bool CommunicationProtocol::checkParameters (const std::string &parameter)
+{
+
+ if (ProtocolDetails::AllowedFields.find (parameter) == ProtocolDetails::AllowedFields.end ())
+ {
+ std::cerr << "The parameter specified [" << parameter << "] cannot be selected (or does not exist)." << std::endl;
+ return false;
+ }
+
+ return true;
+}
+
+std::string CommunicationProtocol::evaluateFilters (const std::list<std::vector<std::string>> &filters)
+{
+ // Switch between operand values
+
+ for (auto filter : filters)
+ {
+ if (filter[0] == "id" and filter[1] == "==")
+ {
+ return filter[2];
+ }
+ else
+ {
+ std::cerr << "So far just one filter is supported [==]" << std::endl;
+ }
+ }
+ return std::string ("");
+}
+
+void
+CommunicationProtocol::timerCallback (ns3::emulator::Emulator &emulator, Server *s, websocketpp::connection_hdl hdl, message_ptr msg, Query query, std::shared_ptr<boost::asio::deadline_timer> subscribeTimer)
+{
+ Query reply = this->makeReplyQuery (query, emulator);
+
+ if (reply.isEmpty ())
+ {
+ std::cerr << "Malformed reply. Closing connection.." << std::endl;
+ return;
+ }
+
+ std::cout << "SENDING: " << reply.toJsonString () << std::endl;
+
+ try
+ {
+ s->send (hdl, reply.toJsonString (), msg->get_opcode ());
+ }
+ catch (...)
+ {
+ std::cerr << "Impossible to connect to the remote endpoint. Closing connection..." << std::endl;
+ return;
+ }
+
+ // Reschedule the timer for 1 second in the future:
+ subscribeTimer->expires_from_now (boost::posix_time::milliseconds (1000));
+ subscribeTimer
+ ->async_wait ([this, &emulator, s, hdl, msg, query, subscribeTimer] (const boost::system::error_code &ec)
+ {
+ if (!ec)
+ {
+ timerCallback (emulator, s, hdl, msg, query, subscribeTimer);
+ }
+ });
+}
+
+void
+CommunicationProtocol::processQuery (Server *s, websocketpp::connection_hdl hdl, message_ptr msg, ns3::emulator::Emulator &emulator, Query query)
+{
+ std::string interface_id;
+
+ std::cout << query.toJsonString () << std::endl;
+
+ const std::string &action = query.getAction ();
+
+ if (!checkAction (action))
+ {
+ std::cout << "Error in the action" << std::endl;
+ return;
+ }
+
+ const std::string &objectName = query.getObjectName ();
+
+ if (!checkObjectName (objectName))
+ {
+ std::cout << "Error in the object name" << std::endl;
+ return;
+ }
+
+ // See the filter for understanding which node update
+ const std::list<std::vector<std::string>> &filters = query.getFilter ();
+
+ for (auto filter : filters)
+ {
+ if (!checkFilter (filter))
+ {
+ std::cout << "Error in the filters." << std::endl;
+ }
+ }
+
+ // Evaluate the filter
+ std::string station = evaluateFilters (filters);
+
+ if (action == *ProtocolDetails::AllowedActions.find ("update"))
+ {
+ // See what update (so far just x and y)
+ const std::map<std::string, std::string> &params = query.getParams ();
+
+ if (objectName == *ProtocolDetails::AllowedObjectName.find ("interface"))
+ {
+
+ if (station != "")
+ {
+
+ for (auto param : params)
+ {
+ if (checkParameters (param.first))
+ {
+
+ if (param.first == *ProtocolDetails::AllowedFields.find ("x"))
+ {
+ emulator.setStationXCoordinate (station, std::stod (param.second));
+ }
+ else if (param.first == *ProtocolDetails::AllowedFields.find ("y"))
+ {
+ emulator.setStationYCoordinate (station, std::stod (param.second));
+ }
+ }
+ }
+ }
+ }
+ }
+ else if (action == *ProtocolDetails::AllowedActions.find ("select"))
+ {
+
+ Query reply = makeReplyQuery (query, emulator);
+ reply.setLast (true);
+ try
+ {
+ s->send (hdl, reply.toJsonString (), msg->get_opcode ());
+ }
+ catch (...)
+ {
+ std::cerr << "Impossible to connect to the remote endpoint. Closing connection..." << std::endl;
+ }
+
+ }
+ else if (action == *ProtocolDetails::AllowedActions.find ("subscribe"))
+ {
+ // Schedule send each second
+ std::shared_ptr<boost::asio::deadline_timer> subscribeTimer = std::make_shared<boost::asio::deadline_timer> (s->get_io_service (), boost::posix_time::milliseconds (1000));
+
+ subscribeTimer
+ ->async_wait ([this, &emulator, s, hdl, msg, query, subscribeTimer] (const boost::system::error_code &ec)
+ {
+ if (!ec)
+ {
+ timerCallback (emulator, s, hdl, msg, query, subscribeTimer);
+ }
+ });
+ }
+}
+
+Query CommunicationProtocol::makeReplyQuery (const Query &request, ns3::emulator::Emulator &emulator)
+{
+ // See the fields to select
+ const std::list<std::string> &fields = request.getFields ();
+ const std::string &objectName = request.getObjectName ();
+ const std::list<std::vector<std::string>> &filters = request.getFilter ();
+
+ // Evaluate the filter
+ std::string station = evaluateFilters (filters);
+
+ if (objectName == "interface")
+ {
+
+ if (station != "")
+ {
+
+ std::string update = *ProtocolDetails::AllowedActions.find ("update");
+ std::string node = *ProtocolDetails::AllowedObjectName.find ("interface");
+
+ std::vector<std::string> parameter;
+ parameter.push_back (*ProtocolDetails::AllowedFields.find ("id"));
+ parameter.push_back (*ProtocolDetails::AllowedOperands.find ("=="));
+ parameter.push_back (station);
+
+ std::list<std::vector<std::string>> fltr;
+ fltr.push_back (parameter);
+
+ std::list<std::string> flds = {};
+
+ std::map<std::string, std::string> prms;
+
+ for (auto field : fields)
+ {
+ if (field == "x" || field == "*")
+ {
+ double x;
+ if (emulator.getStationXCoordinate (station, &x))
+ {
+ prms["x"] = std::to_string (x);
+ }
+ }
+ if (field == "y" || field == "*")
+ {
+ double y;
+ if (emulator.getStationYCoordinate (station, &y))
+ {
+ prms["y"] = std::to_string (y);
+ }
+ }
+ if (field == "rate" || field == "*")
+ {
+ double physicalRate;
+ if (emulator.getTransmissionRate (station, &physicalRate))
+ {
+ prms["rate"] = std::to_string (physicalRate);
+ }
+ }
+ else
+ {
+
+ }
+ }
+
+ return Query (*ProtocolDetails::AllowedActions.find ("update"), *ProtocolDetails::AllowedObjectName
+ .find ("interface"), fltr, prms, flds, false);
+ }
+ }
+
+ // Empty reply
+ return Query ();
+
+}
diff --git a/emu-radio/common-library/communication-protocol.h b/emu-radio/common-library/communication-protocol.h
new file mode 100644
index 00000000..b202d7d2
--- /dev/null
+++ b/emu-radio/common-library/communication-protocol.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef WIFI_EMULATOR_PROTOCOL_H
+#define WIFI_EMULATOR_PROTOCOL_H
+
+#include <string>
+#include <map>
+#include <set>
+#include "query.h"
+#include "emulator.h"
+
+#include "websocket-server.h"
+
+enum ProtocolVersion {
+ CONTROL_PROTOCOL_V1 = 1, CONTROL_PROTOCOL_V2 = 2
+};
+
+typedef struct ProtocolDetails {
+ static std::set<std::string> AllowedObjectName;
+ static std::set<std::string> AllowedFields;
+ static std::set<std::string> AllowedActions;
+// static std::list<std::string> AllowedParameters; // Per action
+ static std::set<std::string> AllowedFilters;
+ static std::set<std::string> AllowedOperands; // Per filter
+} ProtocolDetails;
+
+class CommunicationProtocol {
+ public:
+ CommunicationProtocol (ProtocolVersion version = ProtocolVersion::CONTROL_PROTOCOL_V1);
+
+ bool checkFilter (const std::vector<std::string> &filter);
+
+ bool checkFields (const std::string &field);
+
+ bool checkObjectName (const std::string &objectName);
+
+ bool checkParameters (const std::string &parameter);
+
+ bool checkAction (const std::string &action);
+
+ std::string evaluateFilters (const std::list<std::vector<std::string>> &filters);
+
+ void
+ processQuery (Server *s, websocketpp::connection_hdl hdl, message_ptr msg, ns3::emulator::Emulator &emulator, Query query);
+
+ Query makeReplyQuery (const Query &request, ns3::emulator::Emulator &emulator);
+
+ void
+ timerCallback (ns3::emulator::Emulator &emulator, Server *s, websocketpp::connection_hdl hdl, message_ptr msg, Query query, std::shared_ptr<boost::asio::deadline_timer> subscribeTimer);
+
+ private:
+ ProtocolVersion version;
+};
+
+#endif //WIFI_EMULATOR_PROTOCOL_H
diff --git a/emu-radio/common-library/connection-pool.cc b/emu-radio/common-library/connection-pool.cc
new file mode 100644
index 00000000..85f57084
--- /dev/null
+++ b/emu-radio/common-library/connection-pool.cc
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "connection-pool.h"
+
+namespace ns3
+{
+namespace emulator
+{
+
+ConnectionPool::ConnectionPool (unsigned short tcpPort, unsigned short websocketPort)
+// : m_tcpControlServer(tcpPort)
+ : m_webSocketControlServer (tcpPort)
+{
+}
+
+ConnectionPool &ConnectionPool::startListeners (const HandlerFunction &handler)
+{
+// m_tcpControlServer.setHandler(handler);
+ m_webSocketControlServer.setHandler (handler);
+
+// m_tcpConnectionHandle = std::async(std::launch::async, [this](){
+//
+// this->m_tcpControlServer.start();
+//
+// });
+
+ m_webSocketHandle = std::async (std::launch::async, [this] ()
+ {
+
+ this->m_webSocketControlServer.start ();
+
+ });
+
+ return *this;
+}
+
+ConnectionPool &ConnectionPool::processEvents ()
+{
+// m_tcpConnectionHandle.get();
+ m_webSocketHandle.get ();
+}
+
+} // End namespace emulator
+
+} // End namespace ns3 \ No newline at end of file
diff --git a/emu-radio/common-library/connection-pool.h b/emu-radio/common-library/connection-pool.h
new file mode 100644
index 00000000..f09c6cc8
--- /dev/null
+++ b/emu-radio/common-library/connection-pool.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef WIFI_EMULATOR_CONTROLPROTOCOL_H
+#define WIFI_EMULATOR_CONTROLPROTOCOL_H
+
+#include <future>
+//#include "tcp-server.h"
+#include "websocket-server.h"
+#include <unordered_map>
+
+namespace ns3
+{
+namespace emulator
+{
+
+class ConnectionPool {
+ public:
+ ConnectionPool (unsigned short tcpPort = 12345, unsigned short websocketPort = 23456);
+
+ ConnectionPool &startListeners (const HandlerFunction &handler);
+
+ ConnectionPool &processEvents ();
+
+ private:
+ std::future<void> m_webSocketHandle;
+// std::future<void> m_tcpConnectionHandle;
+
+// TcpServer m_tcpControlServer;
+ WebSocketServer m_webSocketControlServer;
+};
+
+} // End namespace emulator
+} // End namespace ns3
+
+#endif //WIFI_EMULATOR_CONTROLPROTOCOL_H
diff --git a/emu-radio/common-library/emulator.h b/emu-radio/common-library/emulator.h
new file mode 100644
index 00000000..a24edd81
--- /dev/null
+++ b/emu-radio/common-library/emulator.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef RADIO_EMULATION_EMULATOR_H
+#define RADIO_EMULATION_EMULATOR_H
+
+namespace ns3
+{
+namespace emulator
+{
+
+class Emulator {
+ public:
+ virtual ~Emulator ()
+ {
+ }
+
+ virtual std::pair<double, double> getStationCoordinates (const std::string &station) = 0;
+
+ virtual bool setStationCoordinates (const std::string &station, double x, double y) = 0;
+
+ virtual bool setStationXCoordinate (const std::string &station, double x) = 0;
+
+ virtual bool getStationYCoordinate (const std::string &station, double *y) = 0;
+
+ virtual bool getStationXCoordinate (const std::string &station, double *x) = 0;
+
+ virtual bool setStationYCoordinate (const std::string &station, double y) = 0;
+
+ virtual Emulator &
+ moveStationAlongSegment (const std::string &station, double start_x, double start_y, double end_x, double end_y, double duration) = 0;
+
+ virtual bool getTransmissionRate (const std::string &station, double *transmissionRate) = 0;
+
+};
+
+}
+}
+
+#endif //RADIO_EMULATION_EMULATOR_H
diff --git a/emu-radio/common-library/json.h b/emu-radio/common-library/json.h
new file mode 100644
index 00000000..4447412c
--- /dev/null
+++ b/emu-radio/common-library/json.h
@@ -0,0 +1,10794 @@
+/*
+ __ _____ _____ _____
+ __| | __| | | | JSON for Modern C++
+| | |__ | | | | | | version 2.0.7
+|_____|_____|_____|_|___| https://github.com/nlohmann/json
+
+Licensed under the MIT License <http://opensource.org/licenses/MIT>.
+Copyright (c) 2013-2016 Niels Lohmann <http://nlohmann.me>.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#ifndef NLOHMANN_JSON_HPP
+#define NLOHMANN_JSON_HPP
+
+#include <algorithm>
+#include <array>
+#include <cassert>
+#include <cctype>
+#include <ciso646>
+#include <cmath>
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <functional>
+#include <initializer_list>
+#include <iomanip>
+#include <iostream>
+#include <iterator>
+#include <limits>
+#include <locale>
+#include <map>
+#include <memory>
+#include <numeric>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+// exclude unsupported compilers
+#if defined(__clang__)
+ #define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__)
+ #if CLANG_VERSION < 30400
+ #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
+ #endif
+#elif defined(__GNUC__)
+ #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
+ #if GCC_VERSION < 40900
+ #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
+ #endif
+#endif
+
+// disable float-equal warnings on GCC/clang
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+ #pragma GCC diagnostic push
+ #pragma GCC diagnostic ignored "-Wfloat-equal"
+#endif
+
+// allow for portable deprecation warnings
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+ #define JSON_DEPRECATED __attribute__((deprecated))
+#elif defined(_MSC_VER)
+ #define JSON_DEPRECATED __declspec(deprecated)
+#else
+ #define JSON_DEPRECATED
+#endif
+
+/*!
+@brief namespace for Niels Lohmann
+@see https://github.com/nlohmann
+@since version 1.0.0
+*/
+namespace nlohmann
+{
+
+
+/*!
+@brief unnamed namespace with internal helper functions
+@since version 1.0.0
+*/
+namespace
+{
+/*!
+@brief Helper to determine whether there's a key_type for T.
+
+Thus helper is used to tell associative containers apart from other containers
+such as sequence containers. For instance, `std::map` passes the test as it
+contains a `mapped_type`, whereas `std::vector` fails the test.
+
+@sa http://stackoverflow.com/a/7728728/266378
+@since version 1.0.0, overworked in version 2.0.6
+*/
+template<typename T>
+struct has_mapped_type
+{
+ private:
+ template <typename U, typename = typename U::mapped_type>
+ static int detect(U&&);
+
+ static void detect(...);
+ public:
+ static constexpr bool value =
+ std::is_integral<decltype(detect(std::declval<T>()))>::value;
+};
+
+/*!
+@brief helper class to create locales with decimal point
+
+This struct is used a default locale during the JSON serialization. JSON
+requires the decimal point to be `.`, so this function overloads the
+`do_decimal_point()` function to return `.`. This function is called by
+float-to-string conversions to retrieve the decimal separator between integer
+and fractional parts.
+
+@sa https://github.com/nlohmann/json/issues/51#issuecomment-86869315
+@since version 2.0.0
+*/
+struct DecimalSeparator : std::numpunct<char>
+{
+ char do_decimal_point() const
+ {
+ return '.';
+ }
+};
+
+}
+
+/*!
+@brief a class to store JSON values
+
+@tparam ObjectType type for JSON objects (`std::map` by default; will be used
+in @ref object_t)
+@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used
+in @ref array_t)
+@tparam StringType type for JSON strings and object keys (`std::string` by
+default; will be used in @ref string_t)
+@tparam BooleanType type for JSON booleans (`bool` by default; will be used
+in @ref boolean_t)
+@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by
+default; will be used in @ref number_integer_t)
+@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c
+`uint64_t` by default; will be used in @ref number_unsigned_t)
+@tparam NumberFloatType type for JSON floating-point numbers (`double` by
+default; will be used in @ref number_float_t)
+@tparam AllocatorType type of the allocator to use (`std::allocator` by
+default)
+
+@requirement The class satisfies the following concept requirements:
+- Basic
+ - [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible):
+ JSON values can be default constructed. The result will be a JSON null value.
+ - [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible):
+ A JSON value can be constructed from an rvalue argument.
+ - [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible):
+ A JSON value can be copy-constructed from an lvalue expression.
+ - [MoveAssignable](http://en.cppreference.com/w/cpp/concept/MoveAssignable):
+ A JSON value van be assigned from an rvalue argument.
+ - [CopyAssignable](http://en.cppreference.com/w/cpp/concept/CopyAssignable):
+ A JSON value can be copy-assigned from an lvalue expression.
+ - [Destructible](http://en.cppreference.com/w/cpp/concept/Destructible):
+ JSON values can be destructed.
+- Layout
+ - [StandardLayoutType](http://en.cppreference.com/w/cpp/concept/StandardLayoutType):
+ JSON values have
+ [standard layout](http://en.cppreference.com/w/cpp/language/data_members#Standard_layout):
+ All non-static data members are private and standard layout types, the class
+ has no virtual functions or (virtual) base classes.
+- Library-wide
+ - [EqualityComparable](http://en.cppreference.com/w/cpp/concept/EqualityComparable):
+ JSON values can be compared with `==`, see @ref
+ operator==(const_reference,const_reference).
+ - [LessThanComparable](http://en.cppreference.com/w/cpp/concept/LessThanComparable):
+ JSON values can be compared with `<`, see @ref
+ operator<(const_reference,const_reference).
+ - [Swappable](http://en.cppreference.com/w/cpp/concept/Swappable):
+ Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of
+ other compatible types, using unqualified function call @ref swap().
+ - [NullablePointer](http://en.cppreference.com/w/cpp/concept/NullablePointer):
+ JSON values can be compared against `std::nullptr_t` objects which are used
+ to model the `null` value.
+- Container
+ - [Container](http://en.cppreference.com/w/cpp/concept/Container):
+ JSON values can be used like STL containers and provide iterator access.
+ - [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer);
+ JSON values can be used like STL containers and provide reverse iterator
+ access.
+
+@invariant The member variables @a m_value and @a m_type have the following
+relationship:
+- If `m_type == value_t::object`, then `m_value.object != nullptr`.
+- If `m_type == value_t::array`, then `m_value.array != nullptr`.
+- If `m_type == value_t::string`, then `m_value.string != nullptr`.
+The invariants are checked by member function assert_invariant().
+
+@internal
+@note ObjectType trick from http://stackoverflow.com/a/9860911
+@endinternal
+
+@see [RFC 7159: The JavaScript Object Notation (JSON) Data Interchange
+Format](http://rfc7159.net/rfc7159)
+
+@since version 1.0.0
+
+@nosubgrouping
+*/
+template <
+ template<typename U, typename V, typename... Args> class ObjectType = std::map,
+ template<typename U, typename... Args> class ArrayType = std::vector,
+ class StringType = std::string,
+ class BooleanType = bool,
+ class NumberIntegerType = std::int64_t,
+ class NumberUnsignedType = std::uint64_t,
+ class NumberFloatType = double,
+ template<typename U> class AllocatorType = std::allocator
+ >
+class basic_json
+{
+ private:
+ /// workaround type for MSVC
+ using basic_json_t = basic_json<ObjectType, ArrayType, StringType,
+ BooleanType, NumberIntegerType, NumberUnsignedType, NumberFloatType,
+ AllocatorType>;
+
+ public:
+ // forward declarations
+ template<typename Base> class json_reverse_iterator;
+ class json_pointer;
+
+ /////////////////////
+ // container types //
+ /////////////////////
+
+ /// @name container types
+ /// The canonic container types to use @ref basic_json like any other STL
+ /// container.
+ /// @{
+
+ /// the type of elements in a basic_json container
+ using value_type = basic_json;
+
+ /// the type of an element reference
+ using reference = value_type&;
+ /// the type of an element const reference
+ using const_reference = const value_type&;
+
+ /// a type to represent differences between iterators
+ using difference_type = std::ptrdiff_t;
+ /// a type to represent container sizes
+ using size_type = std::size_t;
+
+ /// the allocator type
+ using allocator_type = AllocatorType<basic_json>;
+
+ /// the type of an element pointer
+ using pointer = typename std::allocator_traits<allocator_type>::pointer;
+ /// the type of an element const pointer
+ using const_pointer = typename std::allocator_traits<allocator_type>::const_pointer;
+
+ /// an iterator for a basic_json container
+ class iterator;
+ /// a const iterator for a basic_json container
+ class const_iterator;
+ /// a reverse iterator for a basic_json container
+ using reverse_iterator = json_reverse_iterator<typename basic_json::iterator>;
+ /// a const reverse iterator for a basic_json container
+ using const_reverse_iterator = json_reverse_iterator<typename basic_json::const_iterator>;
+
+ /// @}
+
+
+ /*!
+ @brief returns the allocator associated with the container
+ */
+ static allocator_type get_allocator()
+ {
+ return allocator_type();
+ }
+
+
+ ///////////////////////////
+ // JSON value data types //
+ ///////////////////////////
+
+ /// @name JSON value data types
+ /// The data types to store a JSON value. These types are derived from
+ /// the template arguments passed to class @ref basic_json.
+ /// @{
+
+ /*!
+ @brief a type for an object
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes JSON objects as follows:
+ > An object is an unordered collection of zero or more name/value pairs,
+ > where a name is a string and a value is a string, number, boolean, null,
+ > object, or array.
+
+ To store objects in C++, a type is defined by the template parameters
+ described below.
+
+ @tparam ObjectType the container to store objects (e.g., `std::map` or
+ `std::unordered_map`)
+ @tparam StringType the type of the keys or names (e.g., `std::string`).
+ The comparison function `std::less<StringType>` is used to order elements
+ inside the container.
+ @tparam AllocatorType the allocator to use for objects (e.g.,
+ `std::allocator`)
+
+ #### Default type
+
+ With the default values for @a ObjectType (`std::map`), @a StringType
+ (`std::string`), and @a AllocatorType (`std::allocator`), the default
+ value for @a object_t is:
+
+ @code {.cpp}
+ std::map<
+ std::string, // key_type
+ basic_json, // value_type
+ std::less<std::string>, // key_compare
+ std::allocator<std::pair<const std::string, basic_json>> // allocator_type
+ >
+ @endcode
+
+ #### Behavior
+
+ The choice of @a object_t influences the behavior of the JSON class. With
+ the default type, objects have the following behavior:
+
+ - When all names are unique, objects will be interoperable in the sense
+ that all software implementations receiving that object will agree on
+ the name-value mappings.
+ - When the names within an object are not unique, later stored name/value
+ pairs overwrite previously stored name/value pairs, leaving the used
+ names unique. For instance, `{"key": 1}` and `{"key": 2, "key": 1}` will
+ be treated as equal and both stored as `{"key": 1}`.
+ - Internally, name/value pairs are stored in lexicographical order of the
+ names. Objects will also be serialized (see @ref dump) in this order.
+ For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored
+ and serialized as `{"a": 2, "b": 1}`.
+ - When comparing objects, the order of the name/value pairs is irrelevant.
+ This makes objects interoperable in the sense that they will not be
+ affected by these differences. For instance, `{"b": 1, "a": 2}` and
+ `{"a": 2, "b": 1}` will be treated as equal.
+
+ #### Limits
+
+ [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+ > An implementation may set limits on the maximum depth of nesting.
+
+ In this class, the object's limit of nesting is not constraint explicitly.
+ However, a maximum depth of nesting may be introduced by the compiler or
+ runtime environment. A theoretical limit can be queried by calling the
+ @ref max_size function of a JSON object.
+
+ #### Storage
+
+ Objects are stored as pointers in a @ref basic_json type. That is, for any
+ access to object values, a pointer of type `object_t*` must be
+ dereferenced.
+
+ @sa @ref array_t -- type for an array value
+
+ @since version 1.0.0
+
+ @note The order name/value pairs are added to the object is *not*
+ preserved by the library. Therefore, iterating an object may return
+ name/value pairs in a different order than they were originally stored. In
+ fact, keys will be traversed in alphabetical order as `std::map` with
+ `std::less` is used by default. Please note this behavior conforms to [RFC
+ 7159](http://rfc7159.net/rfc7159), because any order implements the
+ specified "unordered" nature of JSON objects.
+ */
+ using object_t = ObjectType<StringType,
+ basic_json,
+ std::less<StringType>,
+ AllocatorType<std::pair<const StringType,
+ basic_json>>>;
+
+ /*!
+ @brief a type for an array
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes JSON arrays as follows:
+ > An array is an ordered sequence of zero or more values.
+
+ To store objects in C++, a type is defined by the template parameters
+ explained below.
+
+ @tparam ArrayType container type to store arrays (e.g., `std::vector` or
+ `std::list`)
+ @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`)
+
+ #### Default type
+
+ With the default values for @a ArrayType (`std::vector`) and @a
+ AllocatorType (`std::allocator`), the default value for @a array_t is:
+
+ @code {.cpp}
+ std::vector<
+ basic_json, // value_type
+ std::allocator<basic_json> // allocator_type
+ >
+ @endcode
+
+ #### Limits
+
+ [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+ > An implementation may set limits on the maximum depth of nesting.
+
+ In this class, the array's limit of nesting is not constraint explicitly.
+ However, a maximum depth of nesting may be introduced by the compiler or
+ runtime environment. A theoretical limit can be queried by calling the
+ @ref max_size function of a JSON array.
+
+ #### Storage
+
+ Arrays are stored as pointers in a @ref basic_json type. That is, for any
+ access to array values, a pointer of type `array_t*` must be dereferenced.
+
+ @sa @ref object_t -- type for an object value
+
+ @since version 1.0.0
+ */
+ using array_t = ArrayType<basic_json, AllocatorType<basic_json>>;
+
+ /*!
+ @brief a type for a string
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes JSON strings as follows:
+ > A string is a sequence of zero or more Unicode characters.
+
+ To store objects in C++, a type is defined by the template parameter
+ described below. Unicode values are split by the JSON class into
+ byte-sized characters during deserialization.
+
+ @tparam StringType the container to store strings (e.g., `std::string`).
+ Note this container is used for keys/names in objects, see @ref object_t.
+
+ #### Default type
+
+ With the default values for @a StringType (`std::string`), the default
+ value for @a string_t is:
+
+ @code {.cpp}
+ std::string
+ @endcode
+
+ #### String comparison
+
+ [RFC 7159](http://rfc7159.net/rfc7159) states:
+ > Software implementations are typically required to test names of object
+ > members for equality. Implementations that transform the textual
+ > representation into sequences of Unicode code units and then perform the
+ > comparison numerically, code unit by code unit, are interoperable in the
+ > sense that implementations will agree in all cases on equality or
+ > inequality of two strings. For example, implementations that compare
+ > strings with escaped characters unconverted may incorrectly find that
+ > `"a\\b"` and `"a\u005Cb"` are not equal.
+
+ This implementation is interoperable as it does compare strings code unit
+ by code unit.
+
+ #### Storage
+
+ String values are stored as pointers in a @ref basic_json type. That is,
+ for any access to string values, a pointer of type `string_t*` must be
+ dereferenced.
+
+ @since version 1.0.0
+ */
+ using string_t = StringType;
+
+ /*!
+ @brief a type for a boolean
+
+ [RFC 7159](http://rfc7159.net/rfc7159) implicitly describes a boolean as a
+ type which differentiates the two literals `true` and `false`.
+
+ To store objects in C++, a type is defined by the template parameter @a
+ BooleanType which chooses the type to use.
+
+ #### Default type
+
+ With the default values for @a BooleanType (`bool`), the default value for
+ @a boolean_t is:
+
+ @code {.cpp}
+ bool
+ @endcode
+
+ #### Storage
+
+ Boolean values are stored directly inside a @ref basic_json type.
+
+ @since version 1.0.0
+ */
+ using boolean_t = BooleanType;
+
+ /*!
+ @brief a type for a number (integer)
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+ > The representation of numbers is similar to that used in most
+ > programming languages. A number is represented in base 10 using decimal
+ > digits. It contains an integer component that may be prefixed with an
+ > optional minus sign, which may be followed by a fraction part and/or an
+ > exponent part. Leading zeros are not allowed. (...) Numeric values that
+ > cannot be represented in the grammar below (such as Infinity and NaN)
+ > are not permitted.
+
+ This description includes both integer and floating-point numbers.
+ However, C++ allows more precise storage if it is known whether the number
+ is a signed integer, an unsigned integer or a floating-point number.
+ Therefore, three different types, @ref number_integer_t, @ref
+ number_unsigned_t and @ref number_float_t are used.
+
+ To store integer numbers in C++, a type is defined by the template
+ parameter @a NumberIntegerType which chooses the type to use.
+
+ #### Default type
+
+ With the default values for @a NumberIntegerType (`int64_t`), the default
+ value for @a number_integer_t is:
+
+ @code {.cpp}
+ int64_t
+ @endcode
+
+ #### Default behavior
+
+ - The restrictions about leading zeros is not enforced in C++. Instead,
+ leading zeros in integer literals lead to an interpretation as octal
+ number. Internally, the value will be stored as decimal number. For
+ instance, the C++ integer literal `010` will be serialized to `8`.
+ During deserialization, leading zeros yield an error.
+ - Not-a-number (NaN) values will be serialized to `null`.
+
+ #### Limits
+
+ [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+ > An implementation may set limits on the range and precision of numbers.
+
+ When the default type is used, the maximal integer number that can be
+ stored is `9223372036854775807` (INT64_MAX) and the minimal integer number
+ that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers
+ that are out of range will yield over/underflow when used in a
+ constructor. During deserialization, too large or small integer numbers
+ will be automatically be stored as @ref number_unsigned_t or @ref
+ number_float_t.
+
+ [RFC 7159](http://rfc7159.net/rfc7159) further states:
+ > Note that when such software is used, numbers that are integers and are
+ > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
+ > that implementations will agree exactly on their numeric values.
+
+ As this range is a subrange of the exactly supported range [INT64_MIN,
+ INT64_MAX], this class's integer type is interoperable.
+
+ #### Storage
+
+ Integer number values are stored directly inside a @ref basic_json type.
+
+ @sa @ref number_float_t -- type for number values (floating-point)
+
+ @sa @ref number_unsigned_t -- type for number values (unsigned integer)
+
+ @since version 1.0.0
+ */
+ using number_integer_t = NumberIntegerType;
+
+ /*!
+ @brief a type for a number (unsigned)
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+ > The representation of numbers is similar to that used in most
+ > programming languages. A number is represented in base 10 using decimal
+ > digits. It contains an integer component that may be prefixed with an
+ > optional minus sign, which may be followed by a fraction part and/or an
+ > exponent part. Leading zeros are not allowed. (...) Numeric values that
+ > cannot be represented in the grammar below (such as Infinity and NaN)
+ > are not permitted.
+
+ This description includes both integer and floating-point numbers.
+ However, C++ allows more precise storage if it is known whether the number
+ is a signed integer, an unsigned integer or a floating-point number.
+ Therefore, three different types, @ref number_integer_t, @ref
+ number_unsigned_t and @ref number_float_t are used.
+
+ To store unsigned integer numbers in C++, a type is defined by the
+ template parameter @a NumberUnsignedType which chooses the type to use.
+
+ #### Default type
+
+ With the default values for @a NumberUnsignedType (`uint64_t`), the
+ default value for @a number_unsigned_t is:
+
+ @code {.cpp}
+ uint64_t
+ @endcode
+
+ #### Default behavior
+
+ - The restrictions about leading zeros is not enforced in C++. Instead,
+ leading zeros in integer literals lead to an interpretation as octal
+ number. Internally, the value will be stored as decimal number. For
+ instance, the C++ integer literal `010` will be serialized to `8`.
+ During deserialization, leading zeros yield an error.
+ - Not-a-number (NaN) values will be serialized to `null`.
+
+ #### Limits
+
+ [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+ > An implementation may set limits on the range and precision of numbers.
+
+ When the default type is used, the maximal integer number that can be
+ stored is `18446744073709551615` (UINT64_MAX) and the minimal integer
+ number that can be stored is `0`. Integer numbers that are out of range
+ will yield over/underflow when used in a constructor. During
+ deserialization, too large or small integer numbers will be automatically
+ be stored as @ref number_integer_t or @ref number_float_t.
+
+ [RFC 7159](http://rfc7159.net/rfc7159) further states:
+ > Note that when such software is used, numbers that are integers and are
+ > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
+ > that implementations will agree exactly on their numeric values.
+
+ As this range is a subrange (when considered in conjunction with the
+ number_integer_t type) of the exactly supported range [0, UINT64_MAX],
+ this class's integer type is interoperable.
+
+ #### Storage
+
+ Integer number values are stored directly inside a @ref basic_json type.
+
+ @sa @ref number_float_t -- type for number values (floating-point)
+ @sa @ref number_integer_t -- type for number values (integer)
+
+ @since version 2.0.0
+ */
+ using number_unsigned_t = NumberUnsignedType;
+
+ /*!
+ @brief a type for a number (floating-point)
+
+ [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+ > The representation of numbers is similar to that used in most
+ > programming languages. A number is represented in base 10 using decimal
+ > digits. It contains an integer component that may be prefixed with an
+ > optional minus sign, which may be followed by a fraction part and/or an
+ > exponent part. Leading zeros are not allowed. (...) Numeric values that
+ > cannot be represented in the grammar below (such as Infinity and NaN)
+ > are not permitted.
+
+ This description includes both integer and floating-point numbers.
+ However, C++ allows more precise storage if it is known whether the number
+ is a signed integer, an unsigned integer or a floating-point number.
+ Therefore, three different types, @ref number_integer_t, @ref
+ number_unsigned_t and @ref number_float_t are used.
+
+ To store floating-point numbers in C++, a type is defined by the template
+ parameter @a NumberFloatType which chooses the type to use.
+
+ #### Default type
+
+ With the default values for @a NumberFloatType (`double`), the default
+ value for @a number_float_t is:
+
+ @code {.cpp}
+ double
+ @endcode
+
+ #### Default behavior
+
+ - The restrictions about leading zeros is not enforced in C++. Instead,
+ leading zeros in floating-point literals will be ignored. Internally,
+ the value will be stored as decimal number. For instance, the C++
+ floating-point literal `01.2` will be serialized to `1.2`. During
+ deserialization, leading zeros yield an error.
+ - Not-a-number (NaN) values will be serialized to `null`.
+
+ #### Limits
+
+ [RFC 7159](http://rfc7159.net/rfc7159) states:
+ > This specification allows implementations to set limits on the range and
+ > precision of numbers accepted. Since software that implements IEEE
+ > 754-2008 binary64 (double precision) numbers is generally available and
+ > widely used, good interoperability can be achieved by implementations
+ > that expect no more precision or range than these provide, in the sense
+ > that implementations will approximate JSON numbers within the expected
+ > precision.
+
+ This implementation does exactly follow this approach, as it uses double
+ precision floating-point numbers. Note values smaller than
+ `-1.79769313486232e+308` and values greater than `1.79769313486232e+308`
+ will be stored as NaN internally and be serialized to `null`.
+
+ #### Storage
+
+ Floating-point number values are stored directly inside a @ref basic_json
+ type.
+
+ @sa @ref number_integer_t -- type for number values (integer)
+
+ @sa @ref number_unsigned_t -- type for number values (unsigned integer)
+
+ @since version 1.0.0
+ */
+ using number_float_t = NumberFloatType;
+
+ /// @}
+
+
+ ///////////////////////////
+ // JSON type enumeration //
+ ///////////////////////////
+
+ /*!
+ @brief the JSON type enumeration
+
+ This enumeration collects the different JSON types. It is internally used
+ to distinguish the stored values, and the functions @ref is_null(), @ref
+ is_object(), @ref is_array(), @ref is_string(), @ref is_boolean(), @ref
+ is_number() (with @ref is_number_integer(), @ref is_number_unsigned(), and
+ @ref is_number_float()), @ref is_discarded(), @ref is_primitive(), and
+ @ref is_structured() rely on it.
+
+ @note There are three enumeration entries (number_integer,
+ number_unsigned, and number_float), because the library distinguishes
+ these three types for numbers: @ref number_unsigned_t is used for unsigned
+ integers, @ref number_integer_t is used for signed integers, and @ref
+ number_float_t is used for floating-point numbers or to approximate
+ integers which do not fit in the limits of their respective type.
+
+ @sa @ref basic_json(const value_t value_type) -- create a JSON value with
+ the default value for a given type
+
+ @since version 1.0.0
+ */
+ enum class value_t : uint8_t
+ {
+ null, ///< null value
+ object, ///< object (unordered set of name/value pairs)
+ array, ///< array (ordered collection of values)
+ string, ///< string value
+ boolean, ///< boolean value
+ number_integer, ///< number value (signed integer)
+ number_unsigned, ///< number value (unsigned integer)
+ number_float, ///< number value (floating-point)
+ discarded ///< discarded by the the parser callback function
+ };
+
+
+ private:
+
+ /// helper for exception-safe object creation
+ template<typename T, typename... Args>
+ static T* create(Args&& ... args)
+ {
+ AllocatorType<T> alloc;
+ auto deleter = [&](T * object)
+ {
+ alloc.deallocate(object, 1);
+ };
+ std::unique_ptr<T, decltype(deleter)> object(alloc.allocate(1), deleter);
+ alloc.construct(object.get(), std::forward<Args>(args)...);
+ assert(object.get() != nullptr);
+ return object.release();
+ }
+
+ ////////////////////////
+ // JSON value storage //
+ ////////////////////////
+
+ /*!
+ @brief a JSON value
+
+ The actual storage for a JSON value of the @ref basic_json class. This
+ union combines the different storage types for the JSON value types
+ defined in @ref value_t.
+
+ JSON type | value_t type | used type
+ --------- | --------------- | ------------------------
+ object | object | pointer to @ref object_t
+ array | array | pointer to @ref array_t
+ string | string | pointer to @ref string_t
+ boolean | boolean | @ref boolean_t
+ number | number_integer | @ref number_integer_t
+ number | number_unsigned | @ref number_unsigned_t
+ number | number_float | @ref number_float_t
+ null | null | *no value is stored*
+
+ @note Variable-length types (objects, arrays, and strings) are stored as
+ pointers. The size of the union should not exceed 64 bits if the default
+ value types are used.
+
+ @since version 1.0.0
+ */
+ union json_value
+ {
+ /// object (stored with pointer to save storage)
+ object_t* object;
+ /// array (stored with pointer to save storage)
+ array_t* array;
+ /// string (stored with pointer to save storage)
+ string_t* string;
+ /// boolean
+ boolean_t boolean;
+ /// number (integer)
+ number_integer_t number_integer;
+ /// number (unsigned integer)
+ number_unsigned_t number_unsigned;
+ /// number (floating-point)
+ number_float_t number_float;
+
+ /// default constructor (for null values)
+ json_value() = default;
+ /// constructor for booleans
+ json_value(boolean_t v) noexcept : boolean(v) {}
+ /// constructor for numbers (integer)
+ json_value(number_integer_t v) noexcept : number_integer(v) {}
+ /// constructor for numbers (unsigned)
+ json_value(number_unsigned_t v) noexcept : number_unsigned(v) {}
+ /// constructor for numbers (floating-point)
+ json_value(number_float_t v) noexcept : number_float(v) {}
+ /// constructor for empty values of a given type
+ json_value(value_t t)
+ {
+ switch (t)
+ {
+ case value_t::object:
+ {
+ object = create<object_t>();
+ break;
+ }
+
+ case value_t::array:
+ {
+ array = create<array_t>();
+ break;
+ }
+
+ case value_t::string:
+ {
+ string = create<string_t>("");
+ break;
+ }
+
+ case value_t::boolean:
+ {
+ boolean = boolean_t(false);
+ break;
+ }
+
+ case value_t::number_integer:
+ {
+ number_integer = number_integer_t(0);
+ break;
+ }
+
+ case value_t::number_unsigned:
+ {
+ number_unsigned = number_unsigned_t(0);
+ break;
+ }
+
+ case value_t::number_float:
+ {
+ number_float = number_float_t(0.0);
+ break;
+ }
+
+ default:
+ {
+ break;
+ }
+ }
+ }
+
+ /// constructor for strings
+ json_value(const string_t& value)
+ {
+ string = create<string_t>(value);
+ }
+
+ /// constructor for objects
+ json_value(const object_t& value)
+ {
+ object = create<object_t>(value);
+ }
+
+ /// constructor for arrays
+ json_value(const array_t& value)
+ {
+ array = create<array_t>(value);
+ }
+ };
+
+ /*!
+ @brief checks the class invariants
+
+ This function asserts the class invariants. It needs to be called at the
+ end of every constructor to make sure that created objects respect the
+ invariant. Furthermore, it has to be called each time the type of a JSON
+ value is changed, because the invariant expresses a relationship between
+ @a m_type and @a m_value.
+ */
+ void assert_invariant() const
+ {
+ assert(m_type != value_t::object or m_value.object != nullptr);
+ assert(m_type != value_t::array or m_value.array != nullptr);
+ assert(m_type != value_t::string or m_value.string != nullptr);
+ }
+
+ public:
+ //////////////////////////
+ // JSON parser callback //
+ //////////////////////////
+
+ /*!
+ @brief JSON callback events
+
+ This enumeration lists the parser events that can trigger calling a
+ callback function of type @ref parser_callback_t during parsing.
+
+ @image html callback_events.png "Example when certain parse events are triggered"
+
+ @since version 1.0.0
+ */
+ enum class parse_event_t : uint8_t
+ {
+ /// the parser read `{` and started to process a JSON object
+ object_start,
+ /// the parser read `}` and finished processing a JSON object
+ object_end,
+ /// the parser read `[` and started to process a JSON array
+ array_start,
+ /// the parser read `]` and finished processing a JSON array
+ array_end,
+ /// the parser read a key of a value in an object
+ key,
+ /// the parser finished reading a JSON value
+ value
+ };
+
+ /*!
+ @brief per-element parser callback type
+
+ With a parser callback function, the result of parsing a JSON text can be
+ influenced. When passed to @ref parse(std::istream&, const
+ parser_callback_t) or @ref parse(const char*, const parser_callback_t),
+ it is called on certain events (passed as @ref parse_event_t via parameter
+ @a event) with a set recursion depth @a depth and context JSON value
+ @a parsed. The return value of the callback function is a boolean
+ indicating whether the element that emitted the callback shall be kept or
+ not.
+
+ We distinguish six scenarios (determined by the event type) in which the
+ callback function can be called. The following table describes the values
+ of the parameters @a depth, @a event, and @a parsed.
+
+ parameter @a event | description | parameter @a depth | parameter @a parsed
+ ------------------ | ----------- | ------------------ | -------------------
+ parse_event_t::object_start | the parser read `{` and started to process a JSON object | depth of the parent of the JSON object | a JSON value with type discarded
+ parse_event_t::key | the parser read a key of a value in an object | depth of the currently parsed JSON object | a JSON string containing the key
+ parse_event_t::object_end | the parser read `}` and finished processing a JSON object | depth of the parent of the JSON object | the parsed JSON object
+ parse_event_t::array_start | the parser read `[` and started to process a JSON array | depth of the parent of the JSON array | a JSON value with type discarded
+ parse_event_t::array_end | the parser read `]` and finished processing a JSON array | depth of the parent of the JSON array | the parsed JSON array
+ parse_event_t::value | the parser finished reading a JSON value | depth of the value | the parsed JSON value
+
+ @image html callback_events.png "Example when certain parse events are triggered"
+
+ Discarding a value (i.e., returning `false`) has different effects
+ depending on the context in which function was called:
+
+ - Discarded values in structured types are skipped. That is, the parser
+ will behave as if the discarded value was never read.
+ - In case a value outside a structured type is skipped, it is replaced
+ with `null`. This case happens if the top-level element is skipped.
+
+ @param[in] depth the depth of the recursion during parsing
+
+ @param[in] event an event of type parse_event_t indicating the context in
+ the callback function has been called
+
+ @param[in,out] parsed the current intermediate parse result; note that
+ writing to this value has no effect for parse_event_t::key events
+
+ @return Whether the JSON value which called the function during parsing
+ should be kept (`true`) or not (`false`). In the latter case, it is either
+ skipped completely or replaced by an empty discarded object.
+
+ @sa @ref parse(std::istream&, parser_callback_t) or
+ @ref parse(const char*, parser_callback_t) for examples
+
+ @since version 1.0.0
+ */
+ using parser_callback_t = std::function<bool(int depth,
+ parse_event_t event,
+ basic_json& parsed)>;
+
+
+ //////////////////
+ // constructors //
+ //////////////////
+
+ /// @name constructors and destructors
+ /// Constructors of class @ref basic_json, copy/move constructor, copy
+ /// assignment, static functions creating objects, and the destructor.
+ /// @{
+
+ /*!
+ @brief create an empty value with a given type
+
+ Create an empty JSON value with a given type. The value will be default
+ initialized with an empty value which depends on the type:
+
+ Value type | initial value
+ ----------- | -------------
+ null | `null`
+ boolean | `false`
+ string | `""`
+ number | `0`
+ object | `{}`
+ array | `[]`
+
+ @param[in] value_type the type of the value to create
+
+ @complexity Constant.
+
+ @throw std::bad_alloc if allocation for object, array, or string value
+ fails
+
+ @liveexample{The following code shows the constructor for different @ref
+ value_t values,basic_json__value_t}
+
+ @sa @ref basic_json(std::nullptr_t) -- create a `null` value
+ @sa @ref basic_json(boolean_t value) -- create a boolean value
+ @sa @ref basic_json(const string_t&) -- create a string value
+ @sa @ref basic_json(const object_t&) -- create a object value
+ @sa @ref basic_json(const array_t&) -- create a array value
+ @sa @ref basic_json(const number_float_t) -- create a number
+ (floating-point) value
+ @sa @ref basic_json(const number_integer_t) -- create a number (integer)
+ value
+ @sa @ref basic_json(const number_unsigned_t) -- create a number (unsigned)
+ value
+
+ @since version 1.0.0
+ */
+ basic_json(const value_t value_type)
+ : m_type(value_type), m_value(value_type)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a null object
+
+ Create a `null` JSON value. It either takes a null pointer as parameter
+ (explicitly creating `null`) or no parameter (implicitly creating `null`).
+ The passed null pointer itself is not read -- it is only used to choose
+ the right constructor.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this constructor never throws
+ exceptions.
+
+ @liveexample{The following code shows the constructor with and without a
+ null pointer parameter.,basic_json__nullptr_t}
+
+ @since version 1.0.0
+ */
+ basic_json(std::nullptr_t = nullptr) noexcept
+ : basic_json(value_t::null)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an object (explicit)
+
+ Create an object JSON value with a given content.
+
+ @param[in] val a value for the object
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for object value fails
+
+ @liveexample{The following code shows the constructor with an @ref
+ object_t parameter.,basic_json__object_t}
+
+ @sa @ref basic_json(const CompatibleObjectType&) -- create an object value
+ from a compatible STL container
+
+ @since version 1.0.0
+ */
+ basic_json(const object_t& val)
+ : m_type(value_t::object), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an object (implicit)
+
+ Create an object JSON value with a given content. This constructor allows
+ any type @a CompatibleObjectType that can be used to construct values of
+ type @ref object_t.
+
+ @tparam CompatibleObjectType An object type whose `key_type` and
+ `value_type` is compatible to @ref object_t. Examples include `std::map`,
+ `std::unordered_map`, `std::multimap`, and `std::unordered_multimap` with
+ a `key_type` of `std::string`, and a `value_type` from which a @ref
+ basic_json value can be constructed.
+
+ @param[in] val a value for the object
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for object value fails
+
+ @liveexample{The following code shows the constructor with several
+ compatible object type parameters.,basic_json__CompatibleObjectType}
+
+ @sa @ref basic_json(const object_t&) -- create an object value
+
+ @since version 1.0.0
+ */
+ template<class CompatibleObjectType, typename std::enable_if<
+ std::is_constructible<typename object_t::key_type, typename CompatibleObjectType::key_type>::value and
+ std::is_constructible<basic_json, typename CompatibleObjectType::mapped_type>::value, int>::type = 0>
+ basic_json(const CompatibleObjectType& val)
+ : m_type(value_t::object)
+ {
+ using std::begin;
+ using std::end;
+ m_value.object = create<object_t>(begin(val), end(val));
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an array (explicit)
+
+ Create an array JSON value with a given content.
+
+ @param[in] val a value for the array
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for array value fails
+
+ @liveexample{The following code shows the constructor with an @ref array_t
+ parameter.,basic_json__array_t}
+
+ @sa @ref basic_json(const CompatibleArrayType&) -- create an array value
+ from a compatible STL containers
+
+ @since version 1.0.0
+ */
+ basic_json(const array_t& val)
+ : m_type(value_t::array), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an array (implicit)
+
+ Create an array JSON value with a given content. This constructor allows
+ any type @a CompatibleArrayType that can be used to construct values of
+ type @ref array_t.
+
+ @tparam CompatibleArrayType An object type whose `value_type` is
+ compatible to @ref array_t. Examples include `std::vector`, `std::deque`,
+ `std::list`, `std::forward_list`, `std::array`, `std::set`,
+ `std::unordered_set`, `std::multiset`, and `unordered_multiset` with a
+ `value_type` from which a @ref basic_json value can be constructed.
+
+ @param[in] val a value for the array
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for array value fails
+
+ @liveexample{The following code shows the constructor with several
+ compatible array type parameters.,basic_json__CompatibleArrayType}
+
+ @sa @ref basic_json(const array_t&) -- create an array value
+
+ @since version 1.0.0
+ */
+ template<class CompatibleArrayType, typename std::enable_if<
+ not std::is_same<CompatibleArrayType, typename basic_json_t::iterator>::value and
+ not std::is_same<CompatibleArrayType, typename basic_json_t::const_iterator>::value and
+ not std::is_same<CompatibleArrayType, typename basic_json_t::reverse_iterator>::value and
+ not std::is_same<CompatibleArrayType, typename basic_json_t::const_reverse_iterator>::value and
+ not std::is_same<CompatibleArrayType, typename array_t::iterator>::value and
+ not std::is_same<CompatibleArrayType, typename array_t::const_iterator>::value and
+ std::is_constructible<basic_json, typename CompatibleArrayType::value_type>::value, int>::type = 0>
+ basic_json(const CompatibleArrayType& val)
+ : m_type(value_t::array)
+ {
+ using std::begin;
+ using std::end;
+ m_value.array = create<array_t>(begin(val), end(val));
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a string (explicit)
+
+ Create an string JSON value with a given content.
+
+ @param[in] val a value for the string
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for string value fails
+
+ @liveexample{The following code shows the constructor with an @ref
+ string_t parameter.,basic_json__string_t}
+
+ @sa @ref basic_json(const typename string_t::value_type*) -- create a
+ string value from a character pointer
+ @sa @ref basic_json(const CompatibleStringType&) -- create a string value
+ from a compatible string container
+
+ @since version 1.0.0
+ */
+ basic_json(const string_t& val)
+ : m_type(value_t::string), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a string (explicit)
+
+ Create a string JSON value with a given content.
+
+ @param[in] val a literal value for the string
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for string value fails
+
+ @liveexample{The following code shows the constructor with string literal
+ parameter.,basic_json__string_t_value_type}
+
+ @sa @ref basic_json(const string_t&) -- create a string value
+ @sa @ref basic_json(const CompatibleStringType&) -- create a string value
+ from a compatible string container
+
+ @since version 1.0.0
+ */
+ basic_json(const typename string_t::value_type* val)
+ : basic_json(string_t(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a string (implicit)
+
+ Create a string JSON value with a given content.
+
+ @param[in] val a value for the string
+
+ @tparam CompatibleStringType an string type which is compatible to @ref
+ string_t, for instance `std::string`.
+
+ @complexity Linear in the size of the passed @a val.
+
+ @throw std::bad_alloc if allocation for string value fails
+
+ @liveexample{The following code shows the construction of a string value
+ from a compatible type.,basic_json__CompatibleStringType}
+
+ @sa @ref basic_json(const string_t&) -- create a string value
+ @sa @ref basic_json(const typename string_t::value_type*) -- create a
+ string value from a character pointer
+
+ @since version 1.0.0
+ */
+ template<class CompatibleStringType, typename std::enable_if<
+ std::is_constructible<string_t, CompatibleStringType>::value, int>::type = 0>
+ basic_json(const CompatibleStringType& val)
+ : basic_json(string_t(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a boolean (explicit)
+
+ Creates a JSON boolean type from a given value.
+
+ @param[in] val a boolean value to store
+
+ @complexity Constant.
+
+ @liveexample{The example below demonstrates boolean
+ values.,basic_json__boolean_t}
+
+ @since version 1.0.0
+ */
+ basic_json(boolean_t val) noexcept
+ : m_type(value_t::boolean), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an integer number (explicit)
+
+ Create an integer number JSON value with a given content.
+
+ @tparam T A helper type to remove this function via SFINAE in case @ref
+ number_integer_t is the same as `int`. In this case, this constructor
+ would have the same signature as @ref basic_json(const int value). Note
+ the helper type @a T is not visible in this constructor's interface.
+
+ @param[in] val an integer to create a JSON number from
+
+ @complexity Constant.
+
+ @liveexample{The example below shows the construction of an integer
+ number value.,basic_json__number_integer_t}
+
+ @sa @ref basic_json(const int) -- create a number value (integer)
+ @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number
+ value (integer) from a compatible number type
+
+ @since version 1.0.0
+ */
+ template<typename T, typename std::enable_if<
+ not (std::is_same<T, int>::value) and
+ std::is_same<T, number_integer_t>::value, int>::type = 0>
+ basic_json(const number_integer_t val) noexcept
+ : m_type(value_t::number_integer), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an integer number from an enum type (explicit)
+
+ Create an integer number JSON value with a given content.
+
+ @param[in] val an integer to create a JSON number from
+
+ @note This constructor allows to pass enums directly to a constructor. As
+ C++ has no way of specifying the type of an anonymous enum explicitly, we
+ can only rely on the fact that such values implicitly convert to int. As
+ int may already be the same type of number_integer_t, we may need to
+ switch off the constructor @ref basic_json(const number_integer_t).
+
+ @complexity Constant.
+
+ @liveexample{The example below shows the construction of an integer
+ number value from an anonymous enum.,basic_json__const_int}
+
+ @sa @ref basic_json(const number_integer_t) -- create a number value
+ (integer)
+ @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number
+ value (integer) from a compatible number type
+
+ @since version 1.0.0
+ */
+ basic_json(const int val) noexcept
+ : m_type(value_t::number_integer),
+ m_value(static_cast<number_integer_t>(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an integer number (implicit)
+
+ Create an integer number JSON value with a given content. This constructor
+ allows any type @a CompatibleNumberIntegerType that can be used to
+ construct values of type @ref number_integer_t.
+
+ @tparam CompatibleNumberIntegerType An integer type which is compatible to
+ @ref number_integer_t. Examples include the types `int`, `int32_t`,
+ `long`, and `short`.
+
+ @param[in] val an integer to create a JSON number from
+
+ @complexity Constant.
+
+ @liveexample{The example below shows the construction of several integer
+ number values from compatible
+ types.,basic_json__CompatibleIntegerNumberType}
+
+ @sa @ref basic_json(const number_integer_t) -- create a number value
+ (integer)
+ @sa @ref basic_json(const int) -- create a number value (integer)
+
+ @since version 1.0.0
+ */
+ template<typename CompatibleNumberIntegerType, typename std::enable_if<
+ std::is_constructible<number_integer_t, CompatibleNumberIntegerType>::value and
+ std::numeric_limits<CompatibleNumberIntegerType>::is_integer and
+ std::numeric_limits<CompatibleNumberIntegerType>::is_signed,
+ CompatibleNumberIntegerType>::type = 0>
+ basic_json(const CompatibleNumberIntegerType val) noexcept
+ : m_type(value_t::number_integer),
+ m_value(static_cast<number_integer_t>(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an unsigned integer number (explicit)
+
+ Create an unsigned integer number JSON value with a given content.
+
+ @tparam T helper type to compare number_unsigned_t and unsigned int (not
+ visible in) the interface.
+
+ @param[in] val an integer to create a JSON number from
+
+ @complexity Constant.
+
+ @sa @ref basic_json(const CompatibleNumberUnsignedType) -- create a number
+ value (unsigned integer) from a compatible number type
+
+ @since version 2.0.0
+ */
+ template<typename T, typename std::enable_if<
+ not (std::is_same<T, int>::value) and
+ std::is_same<T, number_unsigned_t>::value, int>::type = 0>
+ basic_json(const number_unsigned_t val) noexcept
+ : m_type(value_t::number_unsigned), m_value(val)
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an unsigned number (implicit)
+
+ Create an unsigned number JSON value with a given content. This
+ constructor allows any type @a CompatibleNumberUnsignedType that can be
+ used to construct values of type @ref number_unsigned_t.
+
+ @tparam CompatibleNumberUnsignedType An integer type which is compatible
+ to @ref number_unsigned_t. Examples may include the types `unsigned int`,
+ `uint32_t`, or `unsigned short`.
+
+ @param[in] val an unsigned integer to create a JSON number from
+
+ @complexity Constant.
+
+ @sa @ref basic_json(const number_unsigned_t) -- create a number value
+ (unsigned)
+
+ @since version 2.0.0
+ */
+ template<typename CompatibleNumberUnsignedType, typename std::enable_if <
+ std::is_constructible<number_unsigned_t, CompatibleNumberUnsignedType>::value and
+ std::numeric_limits<CompatibleNumberUnsignedType>::is_integer and
+ not std::numeric_limits<CompatibleNumberUnsignedType>::is_signed,
+ CompatibleNumberUnsignedType>::type = 0>
+ basic_json(const CompatibleNumberUnsignedType val) noexcept
+ : m_type(value_t::number_unsigned),
+ m_value(static_cast<number_unsigned_t>(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a floating-point number (explicit)
+
+ Create a floating-point number JSON value with a given content.
+
+ @param[in] val a floating-point value to create a JSON number from
+
+ @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6
+ disallows NaN values:
+ > Numeric values that cannot be represented in the grammar below (such as
+ > Infinity and NaN) are not permitted.
+ In case the parameter @a val is not a number, a JSON null value is created
+ instead.
+
+ @complexity Constant.
+
+ @liveexample{The following example creates several floating-point
+ values.,basic_json__number_float_t}
+
+ @sa @ref basic_json(const CompatibleNumberFloatType) -- create a number
+ value (floating-point) from a compatible number type
+
+ @since version 1.0.0
+ */
+ basic_json(const number_float_t val) noexcept
+ : m_type(value_t::number_float), m_value(val)
+ {
+ // replace infinity and NAN by null
+ if (not std::isfinite(val))
+ {
+ m_type = value_t::null;
+ m_value = json_value();
+ }
+
+ assert_invariant();
+ }
+
+ /*!
+ @brief create an floating-point number (implicit)
+
+ Create an floating-point number JSON value with a given content. This
+ constructor allows any type @a CompatibleNumberFloatType that can be used
+ to construct values of type @ref number_float_t.
+
+ @tparam CompatibleNumberFloatType A floating-point type which is
+ compatible to @ref number_float_t. Examples may include the types `float`
+ or `double`.
+
+ @param[in] val a floating-point to create a JSON number from
+
+ @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6
+ disallows NaN values:
+ > Numeric values that cannot be represented in the grammar below (such as
+ > Infinity and NaN) are not permitted.
+ In case the parameter @a val is not a number, a JSON null value is
+ created instead.
+
+ @complexity Constant.
+
+ @liveexample{The example below shows the construction of several
+ floating-point number values from compatible
+ types.,basic_json__CompatibleNumberFloatType}
+
+ @sa @ref basic_json(const number_float_t) -- create a number value
+ (floating-point)
+
+ @since version 1.0.0
+ */
+ template<typename CompatibleNumberFloatType, typename = typename std::enable_if<
+ std::is_constructible<number_float_t, CompatibleNumberFloatType>::value and
+ std::is_floating_point<CompatibleNumberFloatType>::value>::type>
+ basic_json(const CompatibleNumberFloatType val) noexcept
+ : basic_json(number_float_t(val))
+ {
+ assert_invariant();
+ }
+
+ /*!
+ @brief create a container (array or object) from an initializer list
+
+ Creates a JSON value of type array or object from the passed initializer
+ list @a init. In case @a type_deduction is `true` (default), the type of
+ the JSON value to be created is deducted from the initializer list @a init
+ according to the following rules:
+
+ 1. If the list is empty, an empty JSON object value `{}` is created.
+ 2. If the list consists of pairs whose first element is a string, a JSON
+ object value is created where the first elements of the pairs are
+ treated as keys and the second elements are as values.
+ 3. In all other cases, an array is created.
+
+ The rules aim to create the best fit between a C++ initializer list and
+ JSON values. The rationale is as follows:
+
+ 1. The empty initializer list is written as `{}` which is exactly an empty
+ JSON object.
+ 2. C++ has now way of describing mapped types other than to list a list of
+ pairs. As JSON requires that keys must be of type string, rule 2 is the
+ weakest constraint one can pose on initializer lists to interpret them
+ as an object.
+ 3. In all other cases, the initializer list could not be interpreted as
+ JSON object type, so interpreting it as JSON array type is safe.
+
+ With the rules described above, the following JSON values cannot be
+ expressed by an initializer list:
+
+ - the empty array (`[]`): use @ref array(std::initializer_list<basic_json>)
+ with an empty initializer list in this case
+ - arrays whose elements satisfy rule 2: use @ref
+ array(std::initializer_list<basic_json>) with the same initializer list
+ in this case
+
+ @note When used without parentheses around an empty initializer list, @ref
+ basic_json() is called instead of this function, yielding the JSON null
+ value.
+
+ @param[in] init initializer list with JSON values
+
+ @param[in] type_deduction internal parameter; when set to `true`, the type
+ of the JSON value is deducted from the initializer list @a init; when set
+ to `false`, the type provided via @a manual_type is forced. This mode is
+ used by the functions @ref array(std::initializer_list<basic_json>) and
+ @ref object(std::initializer_list<basic_json>).
+
+ @param[in] manual_type internal parameter; when @a type_deduction is set
+ to `false`, the created JSON value will use the provided type (only @ref
+ value_t::array and @ref value_t::object are valid); when @a type_deduction
+ is set to `true`, this parameter has no effect
+
+ @throw std::domain_error if @a type_deduction is `false`, @a manual_type
+ is `value_t::object`, but @a init contains an element which is not a pair
+ whose first element is a string; example: `"cannot create object from
+ initializer list"`
+
+ @complexity Linear in the size of the initializer list @a init.
+
+ @liveexample{The example below shows how JSON values are created from
+ initializer lists.,basic_json__list_init_t}
+
+ @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array
+ value from an initializer list
+ @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object
+ value from an initializer list
+
+ @since version 1.0.0
+ */
+ basic_json(std::initializer_list<basic_json> init,
+ bool type_deduction = true,
+ value_t manual_type = value_t::array)
+ {
+ // check if each element is an array with two elements whose first
+ // element is a string
+ bool is_an_object = std::all_of(init.begin(), init.end(),
+ [](const basic_json & element)
+ {
+ return element.is_array() and element.size() == 2 and element[0].is_string();
+ });
+
+ // adjust type if type deduction is not wanted
+ if (not type_deduction)
+ {
+ // if array is wanted, do not create an object though possible
+ if (manual_type == value_t::array)
+ {
+ is_an_object = false;
+ }
+
+ // if object is wanted but impossible, throw an exception
+ if (manual_type == value_t::object and not is_an_object)
+ {
+ throw std::domain_error("cannot create object from initializer list");
+ }
+ }
+
+ if (is_an_object)
+ {
+ // the initializer list is a list of pairs -> create object
+ m_type = value_t::object;
+ m_value = value_t::object;
+
+ std::for_each(init.begin(), init.end(), [this](const basic_json & element)
+ {
+ m_value.object->emplace(*(element[0].m_value.string), element[1]);
+ });
+ }
+ else
+ {
+ // the initializer list describes an array -> create array
+ m_type = value_t::array;
+ m_value.array = create<array_t>(init);
+ }
+
+ assert_invariant();
+ }
+
+ /*!
+ @brief explicitly create an array from an initializer list
+
+ Creates a JSON array value from a given initializer list. That is, given a
+ list of values `a, b, c`, creates the JSON value `[a, b, c]`. If the
+ initializer list is empty, the empty array `[]` is created.
+
+ @note This function is only needed to express two edge cases that cannot
+ be realized with the initializer list constructor (@ref
+ basic_json(std::initializer_list<basic_json>, bool, value_t)). These cases
+ are:
+ 1. creating an array whose elements are all pairs whose first element is a
+ string -- in this case, the initializer list constructor would create an
+ object, taking the first elements as keys
+ 2. creating an empty array -- passing the empty initializer list to the
+ initializer list constructor yields an empty object
+
+ @param[in] init initializer list with JSON values to create an array from
+ (optional)
+
+ @return JSON array value
+
+ @complexity Linear in the size of @a init.
+
+ @liveexample{The following code shows an example for the `array`
+ function.,array}
+
+ @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) --
+ create a JSON value from an initializer list
+ @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object
+ value from an initializer list
+
+ @since version 1.0.0
+ */
+ static basic_json array(std::initializer_list<basic_json> init =
+ std::initializer_list<basic_json>())
+ {
+ return basic_json(init, false, value_t::array);
+ }
+
+ /*!
+ @brief explicitly create an object from an initializer list
+
+ Creates a JSON object value from a given initializer list. The initializer
+ lists elements must be pairs, and their first elements must be strings. If
+ the initializer list is empty, the empty object `{}` is created.
+
+ @note This function is only added for symmetry reasons. In contrast to the
+ related function @ref array(std::initializer_list<basic_json>), there are
+ no cases which can only be expressed by this function. That is, any
+ initializer list @a init can also be passed to the initializer list
+ constructor @ref basic_json(std::initializer_list<basic_json>, bool,
+ value_t).
+
+ @param[in] init initializer list to create an object from (optional)
+
+ @return JSON object value
+
+ @throw std::domain_error if @a init is not a pair whose first elements are
+ strings; thrown by
+ @ref basic_json(std::initializer_list<basic_json>, bool, value_t)
+
+ @complexity Linear in the size of @a init.
+
+ @liveexample{The following code shows an example for the `object`
+ function.,object}
+
+ @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) --
+ create a JSON value from an initializer list
+ @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array
+ value from an initializer list
+
+ @since version 1.0.0
+ */
+ static basic_json object(std::initializer_list<basic_json> init =
+ std::initializer_list<basic_json>())
+ {
+ return basic_json(init, false, value_t::object);
+ }
+
+ /*!
+ @brief construct an array with count copies of given value
+
+ Constructs a JSON array value by creating @a cnt copies of a passed value.
+ In case @a cnt is `0`, an empty array is created. As postcondition,
+ `std::distance(begin(),end()) == cnt` holds.
+
+ @param[in] cnt the number of JSON copies of @a val to create
+ @param[in] val the JSON value to copy
+
+ @complexity Linear in @a cnt.
+
+ @liveexample{The following code shows examples for the @ref
+ basic_json(size_type\, const basic_json&)
+ constructor.,basic_json__size_type_basic_json}
+
+ @since version 1.0.0
+ */
+ basic_json(size_type cnt, const basic_json& val)
+ : m_type(value_t::array)
+ {
+ m_value.array = create<array_t>(cnt, val);
+ assert_invariant();
+ }
+
+ /*!
+ @brief construct a JSON container given an iterator range
+
+ Constructs the JSON value with the contents of the range `[first, last)`.
+ The semantics depends on the different types a JSON value can have:
+ - In case of primitive types (number, boolean, or string), @a first must
+ be `begin()` and @a last must be `end()`. In this case, the value is
+ copied. Otherwise, std::out_of_range is thrown.
+ - In case of structured types (array, object), the constructor behaves as
+ similar versions for `std::vector`.
+ - In case of a null type, std::domain_error is thrown.
+
+ @tparam InputIT an input iterator type (@ref iterator or @ref
+ const_iterator)
+
+ @param[in] first begin of the range to copy from (included)
+ @param[in] last end of the range to copy from (excluded)
+
+ @pre Iterators @a first and @a last must be initialized. **This
+ precondition is enforced with an assertion.**
+
+ @throw std::domain_error if iterators are not compatible; that is, do not
+ belong to the same JSON value; example: `"iterators are not compatible"`
+ @throw std::out_of_range if iterators are for a primitive type (number,
+ boolean, or string) where an out of range error can be detected easily;
+ example: `"iterators out of range"`
+ @throw std::bad_alloc if allocation for object, array, or string fails
+ @throw std::domain_error if called with a null value; example: `"cannot
+ use construct with iterators from null"`
+
+ @complexity Linear in distance between @a first and @a last.
+
+ @liveexample{The example below shows several ways to create JSON values by
+ specifying a subrange with iterators.,basic_json__InputIt_InputIt}
+
+ @since version 1.0.0
+ */
+ template<class InputIT, typename std::enable_if<
+ std::is_same<InputIT, typename basic_json_t::iterator>::value or
+ std::is_same<InputIT, typename basic_json_t::const_iterator>::value, int>::type = 0>
+ basic_json(InputIT first, InputIT last)
+ {
+ assert(first.m_object != nullptr);
+ assert(last.m_object != nullptr);
+
+ // make sure iterator fits the current value
+ if (first.m_object != last.m_object)
+ {
+ throw std::domain_error("iterators are not compatible");
+ }
+
+ // copy type from first iterator
+ m_type = first.m_object->m_type;
+
+ // check if iterator range is complete for primitive values
+ switch (m_type)
+ {
+ case value_t::boolean:
+ case value_t::number_float:
+ case value_t::number_integer:
+ case value_t::number_unsigned:
+ case value_t::string:
+ {
+ if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end())
+ {
+ throw std::out_of_range("iterators out of range");
+ }
+ break;
+ }
+
+ default:
+ {
+ break;
+ }
+ }
+
+ switch (m_type)
+ {
+ case value_t::number_integer:
+ {
+ m_value.number_integer = first.m_object->m_value.number_integer;
+ break;
+ }
+
+ case value_t::number_unsigned:
+ {
+ m_value.number_unsigned = first.m_object->m_value.number_unsigned;
+ break;
+ }
+
+ case value_t::number_float:
+ {
+ m_value.number_float = first.m_object->m_value.number_float;
+ break;
+ }
+
+ case value_t::boolean:
+ {
+ m_value.boolean = first.m_object->m_value.boolean;
+ break;
+ }
+
+ case value_t::string:
+ {
+ m_value = *first.m_object->m_value.string;
+ break;
+ }
+
+ case value_t::object:
+ {
+ m_value.object = create<object_t>(first.m_it.object_iterator, last.m_it.object_iterator);
+ break;
+ }
+
+ case value_t::array:
+ {
+ m_value.array = create<array_t>(first.m_it.array_iterator, last.m_it.array_iterator);
+ break;
+ }
+
+ default:
+ {
+ throw std::domain_error("cannot use construct with iterators from " + first.m_object->type_name());
+ }
+ }
+
+ assert_invariant();
+ }
+
+ /*!
+ @brief construct a JSON value given an input stream
+
+ @param[in,out] i stream to read a serialized JSON value from
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @deprecated This constructor is deprecated and will be removed in version
+ 3.0.0 to unify the interface of the library. Deserialization will be
+ done by stream operators or by calling one of the `parse` functions,
+ e.g. @ref parse(std::istream&, const parser_callback_t). That is, calls
+ like `json j(i);` for an input stream @a i need to be replaced by
+ `json j = json::parse(i);`. See the example below.
+
+ @liveexample{The example below demonstrates constructing a JSON value from
+ a `std::stringstream` with and without callback
+ function.,basic_json__istream}
+
+ @since version 2.0.0, deprecated in version 2.0.3, to be removed in
+ version 3.0.0
+ */
+ JSON_DEPRECATED
+ explicit basic_json(std::istream& i, const parser_callback_t cb = nullptr)
+ {
+ *this = parser(i, cb).parse();
+ assert_invariant();
+ }
+
+ ///////////////////////////////////////
+ // other constructors and destructor //
+ ///////////////////////////////////////
+
+ /*!
+ @brief copy constructor
+
+ Creates a copy of a given JSON value.
+
+ @param[in] other the JSON value to copy
+
+ @complexity Linear in the size of @a other.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is linear.
+ - As postcondition, it holds: `other == basic_json(other)`.
+
+ @throw std::bad_alloc if allocation for object, array, or string fails.
+
+ @liveexample{The following code shows an example for the copy
+ constructor.,basic_json__basic_json}
+
+ @since version 1.0.0
+ */
+ basic_json(const basic_json& other)
+ : m_type(other.m_type)
+ {
+ // check of passed value is valid
+ other.assert_invariant();
+
+ switch (m_type)
+ {
+ case value_t::object:
+ {
+ m_value = *other.m_value.object;
+ break;
+ }
+
+ case value_t::array:
+ {
+ m_value = *other.m_value.array;
+ break;
+ }
+
+ case value_t::string:
+ {
+ m_value = *other.m_value.string;
+ break;
+ }
+
+ case value_t::boolean:
+ {
+ m_value = other.m_value.boolean;
+ break;
+ }
+
+ case value_t::number_integer:
+ {
+ m_value = other.m_value.number_integer;
+ break;
+ }
+
+ case value_t::number_unsigned:
+ {
+ m_value = other.m_value.number_unsigned;
+ break;
+ }
+
+ case value_t::number_float:
+ {
+ m_value = other.m_value.number_float;
+ break;
+ }
+
+ default:
+ {
+ break;
+ }
+ }
+
+ assert_invariant();
+ }
+
+ /*!
+ @brief move constructor
+
+ Move constructor. Constructs a JSON value with the contents of the given
+ value @a other using move semantics. It "steals" the resources from @a
+ other and leaves it as JSON null value.
+
+ @param[in,out] other value to move to this object
+
+ @post @a other is a JSON null value
+
+ @complexity Constant.
+
+ @liveexample{The code below shows the move constructor explicitly called
+ via std::move.,basic_json__moveconstructor}
+
+ @since version 1.0.0
+ */
+ basic_json(basic_json&& other) noexcept
+ : m_type(std::move(other.m_type)),
+ m_value(std::move(other.m_value))
+ {
+ // check that passed value is valid
+ other.assert_invariant();
+
+ // invalidate payload
+ other.m_type = value_t::null;
+ other.m_value = {};
+
+ assert_invariant();
+ }
+
+ /*!
+ @brief copy assignment
+
+ Copy assignment operator. Copies a JSON value via the "copy and swap"
+ strategy: It is expressed in terms of the copy constructor, destructor,
+ and the swap() member function.
+
+ @param[in] other value to copy from
+
+ @complexity Linear.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is linear.
+
+ @liveexample{The code below shows and example for the copy assignment. It
+ creates a copy of value `a` which is then swapped with `b`. Finally\, the
+ copy of `a` (which is the null value after the swap) is
+ destroyed.,basic_json__copyassignment}
+
+ @since version 1.0.0
+ */
+ reference& operator=(basic_json other) noexcept (
+ std::is_nothrow_move_constructible<value_t>::value and
+ std::is_nothrow_move_assignable<value_t>::value and
+ std::is_nothrow_move_constructible<json_value>::value and
+ std::is_nothrow_move_assignable<json_value>::value
+ )
+ {
+ // check that passed value is valid
+ other.assert_invariant();
+
+ using std::swap;
+ swap(m_type, other.m_type);
+ swap(m_value, other.m_value);
+
+ assert_invariant();
+ return *this;
+ }
+
+ /*!
+ @brief destructor
+
+ Destroys the JSON value and frees all allocated memory.
+
+ @complexity Linear.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is linear.
+ - All stored elements are destroyed and all memory is freed.
+
+ @since version 1.0.0
+ */
+ ~basic_json()
+ {
+ assert_invariant();
+
+ switch (m_type)
+ {
+ case value_t::object:
+ {
+ AllocatorType<object_t> alloc;
+ alloc.destroy(m_value.object);
+ alloc.deallocate(m_value.object, 1);
+ break;
+ }
+
+ case value_t::array:
+ {
+ AllocatorType<array_t> alloc;
+ alloc.destroy(m_value.array);
+ alloc.deallocate(m_value.array, 1);
+ break;
+ }
+
+ case value_t::string:
+ {
+ AllocatorType<string_t> alloc;
+ alloc.destroy(m_value.string);
+ alloc.deallocate(m_value.string, 1);
+ break;
+ }
+
+ default:
+ {
+ // all other types need no specific destructor
+ break;
+ }
+ }
+ }
+
+ /// @}
+
+ public:
+ ///////////////////////
+ // object inspection //
+ ///////////////////////
+
+ /// @name object inspection
+ /// Functions to inspect the type of a JSON value.
+ /// @{
+
+ /*!
+ @brief serialization
+
+ Serialization function for JSON values. The function tries to mimic
+ Python's `json.dumps()` function, and currently supports its @a indent
+ parameter.
+
+ @param[in] indent If indent is nonnegative, then array elements and object
+ members will be pretty-printed with that indent level. An indent level of
+ `0` will only insert newlines. `-1` (the default) selects the most compact
+ representation.
+
+ @return string containing the serialization of the JSON value
+
+ @complexity Linear.
+
+ @liveexample{The following example shows the effect of different @a indent
+ parameters to the result of the serialization.,dump}
+
+ @see https://docs.python.org/2/library/json.html#json.dump
+
+ @since version 1.0.0
+ */
+ string_t dump(const int indent = -1) const
+ {
+ std::stringstream ss;
+ // fix locale problems
+ const static std::locale loc(std::locale(), new DecimalSeparator);
+ ss.imbue(loc);
+
+ // 6, 15 or 16 digits of precision allows round-trip IEEE 754
+ // string->float->string, string->double->string or string->long
+ // double->string; to be safe, we read this value from
+ // std::numeric_limits<number_float_t>::digits10
+ ss.precision(std::numeric_limits<double>::digits10);
+
+ if (indent >= 0)
+ {
+ dump(ss, true, static_cast<unsigned int>(indent));
+ }
+ else
+ {
+ dump(ss, false, 0);
+ }
+
+ return ss.str();
+ }
+
+ /*!
+ @brief return the type of the JSON value (explicit)
+
+ Return the type of the JSON value as a value from the @ref value_t
+ enumeration.
+
+ @return the type of the JSON value
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `type()` for all JSON
+ types.,type}
+
+ @since version 1.0.0
+ */
+ constexpr value_t type() const noexcept
+ {
+ return m_type;
+ }
+
+ /*!
+ @brief return whether type is primitive
+
+ This function returns true iff the JSON type is primitive (string, number,
+ boolean, or null).
+
+ @return `true` if type is primitive (string, number, boolean, or null),
+ `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_primitive()` for all JSON
+ types.,is_primitive}
+
+ @sa @ref is_structured() -- returns whether JSON value is structured
+ @sa @ref is_null() -- returns whether JSON value is `null`
+ @sa @ref is_string() -- returns whether JSON value is a string
+ @sa @ref is_boolean() -- returns whether JSON value is a boolean
+ @sa @ref is_number() -- returns whether JSON value is a number
+
+ @since version 1.0.0
+ */
+ constexpr bool is_primitive() const noexcept
+ {
+ return is_null() or is_string() or is_boolean() or is_number();
+ }
+
+ /*!
+ @brief return whether type is structured
+
+ This function returns true iff the JSON type is structured (array or
+ object).
+
+ @return `true` if type is structured (array or object), `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_structured()` for all JSON
+ types.,is_structured}
+
+ @sa @ref is_primitive() -- returns whether value is primitive
+ @sa @ref is_array() -- returns whether value is an array
+ @sa @ref is_object() -- returns whether value is an object
+
+ @since version 1.0.0
+ */
+ constexpr bool is_structured() const noexcept
+ {
+ return is_array() or is_object();
+ }
+
+ /*!
+ @brief return whether value is null
+
+ This function returns true iff the JSON value is null.
+
+ @return `true` if type is null, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_null()` for all JSON
+ types.,is_null}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_null() const noexcept
+ {
+ return m_type == value_t::null;
+ }
+
+ /*!
+ @brief return whether value is a boolean
+
+ This function returns true iff the JSON value is a boolean.
+
+ @return `true` if type is boolean, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_boolean()` for all JSON
+ types.,is_boolean}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_boolean() const noexcept
+ {
+ return m_type == value_t::boolean;
+ }
+
+ /*!
+ @brief return whether value is a number
+
+ This function returns true iff the JSON value is a number. This includes
+ both integer and floating-point values.
+
+ @return `true` if type is number (regardless whether integer, unsigned
+ integer or floating-type), `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_number()` for all JSON
+ types.,is_number}
+
+ @sa @ref is_number_integer() -- check if value is an integer or unsigned
+ integer number
+ @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+ number
+ @sa @ref is_number_float() -- check if value is a floating-point number
+
+ @since version 1.0.0
+ */
+ constexpr bool is_number() const noexcept
+ {
+ return is_number_integer() or is_number_float();
+ }
+
+ /*!
+ @brief return whether value is an integer number
+
+ This function returns true iff the JSON value is an integer or unsigned
+ integer number. This excludes floating-point values.
+
+ @return `true` if type is an integer or unsigned integer number, `false`
+ otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_number_integer()` for all
+ JSON types.,is_number_integer}
+
+ @sa @ref is_number() -- check if value is a number
+ @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+ number
+ @sa @ref is_number_float() -- check if value is a floating-point number
+
+ @since version 1.0.0
+ */
+ constexpr bool is_number_integer() const noexcept
+ {
+ return m_type == value_t::number_integer or m_type == value_t::number_unsigned;
+ }
+
+ /*!
+ @brief return whether value is an unsigned integer number
+
+ This function returns true iff the JSON value is an unsigned integer
+ number. This excludes floating-point and (signed) integer values.
+
+ @return `true` if type is an unsigned integer number, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_number_unsigned()` for all
+ JSON types.,is_number_unsigned}
+
+ @sa @ref is_number() -- check if value is a number
+ @sa @ref is_number_integer() -- check if value is an integer or unsigned
+ integer number
+ @sa @ref is_number_float() -- check if value is a floating-point number
+
+ @since version 2.0.0
+ */
+ constexpr bool is_number_unsigned() const noexcept
+ {
+ return m_type == value_t::number_unsigned;
+ }
+
+ /*!
+ @brief return whether value is a floating-point number
+
+ This function returns true iff the JSON value is a floating-point number.
+ This excludes integer and unsigned integer values.
+
+ @return `true` if type is a floating-point number, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_number_float()` for all
+ JSON types.,is_number_float}
+
+ @sa @ref is_number() -- check if value is number
+ @sa @ref is_number_integer() -- check if value is an integer number
+ @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+ number
+
+ @since version 1.0.0
+ */
+ constexpr bool is_number_float() const noexcept
+ {
+ return m_type == value_t::number_float;
+ }
+
+ /*!
+ @brief return whether value is an object
+
+ This function returns true iff the JSON value is an object.
+
+ @return `true` if type is object, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_object()` for all JSON
+ types.,is_object}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_object() const noexcept
+ {
+ return m_type == value_t::object;
+ }
+
+ /*!
+ @brief return whether value is an array
+
+ This function returns true iff the JSON value is an array.
+
+ @return `true` if type is array, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_array()` for all JSON
+ types.,is_array}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_array() const noexcept
+ {
+ return m_type == value_t::array;
+ }
+
+ /*!
+ @brief return whether value is a string
+
+ This function returns true iff the JSON value is a string.
+
+ @return `true` if type is string, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_string()` for all JSON
+ types.,is_string}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_string() const noexcept
+ {
+ return m_type == value_t::string;
+ }
+
+ /*!
+ @brief return whether value is discarded
+
+ This function returns true iff the JSON value was discarded during parsing
+ with a callback function (see @ref parser_callback_t).
+
+ @note This function will always be `false` for JSON values after parsing.
+ That is, discarded values can only occur during parsing, but will be
+ removed when inside a structured value or replaced by null in other cases.
+
+ @return `true` if type is discarded, `false` otherwise.
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies `is_discarded()` for all JSON
+ types.,is_discarded}
+
+ @since version 1.0.0
+ */
+ constexpr bool is_discarded() const noexcept
+ {
+ return m_type == value_t::discarded;
+ }
+
+ /*!
+ @brief return the type of the JSON value (implicit)
+
+ Implicitly return the type of the JSON value as a value from the @ref
+ value_t enumeration.
+
+ @return the type of the JSON value
+
+ @complexity Constant.
+
+ @exceptionsafety No-throw guarantee: this member function never throws
+ exceptions.
+
+ @liveexample{The following code exemplifies the @ref value_t operator for
+ all JSON types.,operator__value_t}
+
+ @since version 1.0.0
+ */
+ constexpr operator value_t() const noexcept
+ {
+ return m_type;
+ }
+
+ /// @}
+
+ private:
+ //////////////////
+ // value access //
+ //////////////////
+
+ /// get an object (explicit)
+ template<class T, typename std::enable_if<
+ std::is_convertible<typename object_t::key_type, typename T::key_type>::value and
+ std::is_convertible<basic_json_t, typename T::mapped_type>::value, int>::type = 0>
+ T get_impl(T*) const
+ {
+ if (is_object())
+ {
+ return T(m_value.object->begin(), m_value.object->end());
+ }
+ else
+ {
+ throw std::domain_error("type must be object, but is " + type_name());
+ }
+ }
+
+ /// get an object (explicit)
+ object_t get_impl(object_t*) const
+ {
+ if (is_object())
+ {
+ return *(m_value.object);
+ }
+ else
+ {
+ throw std::domain_error("type must be object, but is " + type_name());
+ }
+ }
+
+ /// get an array (explicit)
+ template<class T, typename std::enable_if<
+ std::is_convertible<basic_json_t, typename T::value_type>::value and
+ not std::is_same<basic_json_t, typename T::value_type>::value and
+ not std::is_arithmetic<T>::value and
+ not std::is_convertible<std::string, T>::value and
+ not has_mapped_type<T>::value, int>::type = 0>
+ T get_impl(T*) const
+ {
+ if (is_array())
+ {
+ T to_vector;
+ std::transform(m_value.array->begin(), m_value.array->end(),
+ std::inserter(to_vector, to_vector.end()), [](basic_json i)
+ {
+ return i.get<typename T::value_type>();
+ });
+ return to_vector;
+ }
+ else
+ {
+ throw std::domain_error("type must be array, but is " + type_name());
+ }
+ }
+
+ /// get an array (explicit)
+ template<class T, typename std::enable_if<
+ std::is_convertible<basic_json_t, T>::value and
+ not std::is_same<basic_json_t, T>::value, int>::type = 0>
+ std::vector<T> get_impl(std::vector<T>*) const
+ {
+ if (is_array())
+ {
+ std::vector<T> to_vector;
+ to_vector.reserve(m_value.array->size());
+ std::transform(m_value.array->begin(), m_value.array->end(),
+ std::inserter(to_vector, to_vector.end()), [](basic_json i)
+ {
+ return i.get<T>();
+ });
+ return to_vector;
+ }
+ else
+ {
+ throw std::domain_error("type must be array, but is " + type_name());
+ }
+ }
+
+ /// get an array (explicit)
+ template<class T, typename std::enable_if<
+ std::is_same<basic_json, typename T::value_type>::value and
+ not has_mapped_type<T>::value, int>::type = 0>
+ T get_impl(T*) const
+ {
+ if (is_array())
+ {
+ return T(m_value.array->begin(), m_value.array->end());
+ }
+ else
+ {
+ throw std::domain_error("type must be array, but is " + type_name());
+ }
+ }
+
+ /// get an array (explicit)
+ array_t get_impl(array_t*) const
+ {
+ if (is_array())
+ {
+ return *(m_value.array);
+ }
+ else
+ {
+ throw std::domain_error("type must be array, but is " + type_name());
+ }
+ }
+
+ /// get a string (explicit)
+ template<typename T, typename std::enable_if<
+ std::is_convertible<string_t, T>::value, int>::type = 0>
+ T get_impl(T*) const
+ {
+ if (is_string())
+ {
+ return *m_value.string;
+ }
+ else
+ {
+ throw std::domain_error("type must be string, but is " + type_name());
+ }
+ }
+
+ /// get a number (explicit)
+ template<typename T, typename std::enable_if<
+ std::is_arithmetic<T>::value, int>::type = 0>
+ T get_impl(T*) const
+ {
+ switch (m_type)
+ {
+ case value_t::number_integer:
+ {
+ return static_cast<T>(m_value.number_integer);
+ }
+
+ case value_t::number_unsigned:
+ {
+ return static_cast<T>(m_value.number_unsigned);
+ }
+
+ case value_t::number_float:
+ {
+ return static_cast<T>(m_value.number_float);
+ }
+
+ default:
+ {
+ throw std::domain_error("type must be number, but is " + type_name());
+ }
+ }
+ }
+
+ /// get a boolean (explicit)
+ constexpr boolean_t get_impl(boolean_t*) const
+ {
+ return is_boolean()
+ ? m_value.boolean
+ : throw std::domain_error("type must be boolean, but is " + type_name());
+ }
+
+ /// get a pointer to the value (object)
+ object_t* get_impl_ptr(object_t*) noexcept
+ {
+ return is_object() ? m_value.object : nullptr;
+ }
+
+ /// get a pointer to the value (object)
+ constexpr const object_t* get_impl_ptr(const object_t*) const noexcept
+ {
+ return is_object() ? m_value.object : nullptr;
+ }
+
+ /// get a pointer to the value (array)
+ array_t* get_impl_ptr(array_t*) noexcept
+ {
+ return is_array() ? m_value.array : nullptr;
+ }
+
+ /// get a pointer to the value (array)
+ constexpr const array_t* get_impl_ptr(const array_t*) const noexcept
+ {
+ return is_array() ? m_value.array : nullptr;
+ }
+
+ /// get a pointer to the value (string)
+ string_t* get_impl_ptr(string_t*) noexcept
+ {
+ return is_string() ? m_value.string : nullptr;
+ }
+
+ /// get a pointer to the value (string)
+ constexpr const string_t* get_impl_ptr(const string_t*) const noexcept
+ {
+ return is_string() ? m_value.string : nullptr;
+ }
+
+ /// get a pointer to the value (boolean)
+ boolean_t* get_impl_ptr(boolean_t*) noexcept
+ {
+ return is_boolean() ? &m_value.boolean : nullptr;
+ }
+
+ /// get a pointer to the value (boolean)
+ constexpr const boolean_t* get_impl_ptr(const boolean_t*) const noexcept
+ {
+ return is_boolean() ? &m_value.boolean : nullptr;
+ }
+
+ /// get a pointer to the value (integer number)
+ number_integer_t* get_impl_ptr(number_integer_t*) noexcept
+ {
+ return is_number_integer() ? &m_value.number_integer : nullptr;
+ }
+
+ /// get a pointer to the value (integer number)
+ constexpr const number_integer_t* get_impl_ptr(const number_integer_t*) const noexcept
+ {
+ return is_number_integer() ? &m_value.number_integer : nullptr;
+ }
+
+ /// get a pointer to the value (unsigned number)
+ number_unsigned_t* get_impl_ptr(number_unsigned_t*) noexcept
+ {
+ return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
+ }
+
+ /// get a pointer to the value (unsigned number)
+ constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t*) const noexcept
+ {
+ return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
+ }
+
+ /// get a pointer to the value (floating-point number)
+ number_float_t* get_impl_ptr(number_float_t*) noexcept
+ {
+ return is_number_float() ? &m_value.number_float : nullptr;
+ }
+
+ /// get a pointer to the value (floating-point number)
+ constexpr const number_float_t* get_impl_ptr(const number_float_t*) const noexcept
+ {
+ return is_number_float() ? &m_value.number_float : nullptr;
+ }
+
+ /*!
+ @brief helper function to implement get_ref()
+
+ This funcion helps to implement get_ref() without code duplication for
+ const and non-const overloads
+
+ @tparam ThisType will be deduced as `basic_json` or `const basic_json`
+
+ @throw std::domain_error if ReferenceType does not match underlying value
+ type of the current JSON
+ */
+ template<typename ReferenceType, typename ThisType>
+ static ReferenceType get_ref_impl(ThisType& obj)
+ {
+ // helper type
+ using PointerType = typename std::add_pointer<ReferenceType>::type;
+
+ // delegate the call to get_ptr<>()
+ auto ptr = obj.template get_ptr<PointerType>();
+
+ if (ptr != nullptr)
+ {
+ return *ptr;
+ }
+ else
+ {
+ throw std::domain_error("incompatible ReferenceType for get_ref, actual type is " +
+ obj.type_name());
+ }
+ }
+
+ public:
+
+ /// @name value access
+ /// Direct access to the stored value of a JSON value.
+ /// @{
+
+ /*!
+ @brief get a value (explicit)
+
+ Explicit type conversion between the JSON value and a compatible value.
+
+ @tparam ValueType non-pointer type compatible to the JSON value, for
+ instance `int` for JSON integer numbers, `bool` for JSON booleans, or
+ `std::vector` types for JSON arrays
+
+ @return copy of the JSON value, converted to type @a ValueType
+
+ @throw std::domain_error in case passed type @a ValueType is incompatible
+ to JSON; example: `"type must be object, but is null"`
+
+ @complexity Linear in the size of the JSON value.
+
+ @liveexample{The example below shows several conversions from JSON values
+ to other types. There a few things to note: (1) Floating-point numbers can
+ be converted to integers\, (2) A JSON array can be converted to a standard
+ `std::vector<short>`\, (3) A JSON object can be converted to C++
+ associative containers such as `std::unordered_map<std::string\,
+ json>`.,get__ValueType_const}
+
+ @internal
+ The idea of using a casted null pointer to choose the correct
+ implementation is from <http://stackoverflow.com/a/8315197/266378>.
+ @endinternal
+
+ @sa @ref operator ValueType() const for implicit conversion
+ @sa @ref get() for pointer-member access
+
+ @since version 1.0.0
+ */
+ template<typename ValueType, typename std::enable_if<
+ not std::is_pointer<ValueType>::value, int>::type = 0>
+ ValueType get() const
+ {
+ return get_impl(static_cast<ValueType*>(nullptr));
+ }
+
+ /*!
+ @brief get a pointer value (explicit)
+
+ Explicit pointer access to the internally stored JSON value. No copies are
+ made.
+
+ @warning The pointer becomes invalid if the underlying JSON object
+ changes.
+
+ @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
+ object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
+ @ref number_unsigned_t, or @ref number_float_t.
+
+ @return pointer to the internally stored JSON value if the requested
+ pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how pointers to internal values of a
+ JSON value can be requested. Note that no type conversions are made and a
+ `nullptr` is returned if the value and the requested pointer type does not
+ match.,get__PointerType}
+
+ @sa @ref get_ptr() for explicit pointer-member access
+
+ @since version 1.0.0
+ */
+ template<typename PointerType, typename std::enable_if<
+ std::is_pointer<PointerType>::value, int>::type = 0>
+ PointerType get() noexcept
+ {
+ // delegate the call to get_ptr
+ return get_ptr<PointerType>();
+ }
+
+ /*!
+ @brief get a pointer value (explicit)
+ @copydoc get()
+ */
+ template<typename PointerType, typename std::enable_if<
+ std::is_pointer<PointerType>::value, int>::type = 0>
+ constexpr const PointerType get() const noexcept
+ {
+ // delegate the call to get_ptr
+ return get_ptr<PointerType>();
+ }
+
+ /*!
+ @brief get a pointer value (implicit)
+
+ Implicit pointer access to the internally stored JSON value. No copies are
+ made.
+
+ @warning Writing data to the pointee of the result yields an undefined
+ state.
+
+ @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
+ object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
+ @ref number_unsigned_t, or @ref number_float_t. Enforced by a static
+ assertion.
+
+ @return pointer to the internally stored JSON value if the requested
+ pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how pointers to internal values of a
+ JSON value can be requested. Note that no type conversions are made and a
+ `nullptr` is returned if the value and the requested pointer type does not
+ match.,get_ptr}
+
+ @since version 1.0.0
+ */
+ template<typename PointerType, typename std::enable_if<
+ std::is_pointer<PointerType>::value, int>::type = 0>
+ PointerType get_ptr() noexcept
+ {
+ // get the type of the PointerType (remove pointer and const)
+ using pointee_t = typename std::remove_const<typename
+ std::remove_pointer<typename
+ std::remove_const<PointerType>::type>::type>::type;
+ // make sure the type matches the allowed types
+ static_assert(
+ std::is_same<object_t, pointee_t>::value
+ or std::is_same<array_t, pointee_t>::value
+ or std::is_same<string_t, pointee_t>::value
+ or std::is_same<boolean_t, pointee_t>::value
+ or std::is_same<number_integer_t, pointee_t>::value
+ or std::is_same<number_unsigned_t, pointee_t>::value
+ or std::is_same<number_float_t, pointee_t>::value
+ , "incompatible pointer type");
+
+ // delegate the call to get_impl_ptr<>()
+ return get_impl_ptr(static_cast<PointerType>(nullptr));
+ }
+
+ /*!
+ @brief get a pointer value (implicit)
+ @copydoc get_ptr()
+ */
+ template<typename PointerType, typename std::enable_if<
+ std::is_pointer<PointerType>::value and
+ std::is_const<typename std::remove_pointer<PointerType>::type>::value, int>::type = 0>
+ constexpr const PointerType get_ptr() const noexcept
+ {
+ // get the type of the PointerType (remove pointer and const)
+ using pointee_t = typename std::remove_const<typename
+ std::remove_pointer<typename
+ std::remove_const<PointerType>::type>::type>::type;
+ // make sure the type matches the allowed types
+ static_assert(
+ std::is_same<object_t, pointee_t>::value
+ or std::is_same<array_t, pointee_t>::value
+ or std::is_same<string_t, pointee_t>::value
+ or std::is_same<boolean_t, pointee_t>::value
+ or std::is_same<number_integer_t, pointee_t>::value
+ or std::is_same<number_unsigned_t, pointee_t>::value
+ or std::is_same<number_float_t, pointee_t>::value
+ , "incompatible pointer type");
+
+ // delegate the call to get_impl_ptr<>() const
+ return get_impl_ptr(static_cast<const PointerType>(nullptr));
+ }
+
+ /*!
+ @brief get a reference value (implicit)
+
+ Implict reference access to the internally stored JSON value. No copies
+ are made.
+
+ @warning Writing data to the referee of the result yields an undefined
+ state.
+
+ @tparam ReferenceType reference type; must be a reference to @ref array_t,
+ @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or
+ @ref number_float_t. Enforced by static assertion.
+
+ @return reference to the internally stored JSON value if the requested
+ reference type @a ReferenceType fits to the JSON value; throws
+ std::domain_error otherwise
+
+ @throw std::domain_error in case passed type @a ReferenceType is
+ incompatible with the stored JSON value
+
+ @complexity Constant.
+
+ @liveexample{The example shows several calls to `get_ref()`.,get_ref}
+
+ @since version 1.1.0
+ */
+ template<typename ReferenceType, typename std::enable_if<
+ std::is_reference<ReferenceType>::value, int>::type = 0>
+ ReferenceType get_ref()
+ {
+ // delegate call to get_ref_impl
+ return get_ref_impl<ReferenceType>(*this);
+ }
+
+ /*!
+ @brief get a reference value (implicit)
+ @copydoc get_ref()
+ */
+ template<typename ReferenceType, typename std::enable_if<
+ std::is_reference<ReferenceType>::value and
+ std::is_const<typename std::remove_reference<ReferenceType>::type>::value, int>::type = 0>
+ ReferenceType get_ref() const
+ {
+ // delegate call to get_ref_impl
+ return get_ref_impl<ReferenceType>(*this);
+ }
+
+ /*!
+ @brief get a value (implicit)
+
+ Implicit type conversion between the JSON value and a compatible value.
+ The call is realized by calling @ref get() const.
+
+ @tparam ValueType non-pointer type compatible to the JSON value, for
+ instance `int` for JSON integer numbers, `bool` for JSON booleans, or
+ `std::vector` types for JSON arrays. The character type of @ref string_t
+ as well as an initializer list of this type is excluded to avoid
+ ambiguities as these types implicitly convert to `std::string`.
+
+ @return copy of the JSON value, converted to type @a ValueType
+
+ @throw std::domain_error in case passed type @a ValueType is incompatible
+ to JSON, thrown by @ref get() const
+
+ @complexity Linear in the size of the JSON value.
+
+ @liveexample{The example below shows several conversions from JSON values
+ to other types. There a few things to note: (1) Floating-point numbers can
+ be converted to integers\, (2) A JSON array can be converted to a standard
+ `std::vector<short>`\, (3) A JSON object can be converted to C++
+ associative containers such as `std::unordered_map<std::string\,
+ json>`.,operator__ValueType}
+
+ @since version 1.0.0
+ */
+ template < typename ValueType, typename std::enable_if <
+ not std::is_pointer<ValueType>::value and
+ not std::is_same<ValueType, typename string_t::value_type>::value
+#ifndef _MSC_VER // Fix for issue #167 operator<< abiguity under VS2015
+ and not std::is_same<ValueType, std::initializer_list<typename string_t::value_type>>::value
+#endif
+ , int >::type = 0 >
+ operator ValueType() const
+ {
+ // delegate the call to get<>() const
+ return get<ValueType>();
+ }
+
+ /// @}
+
+
+ ////////////////////
+ // element access //
+ ////////////////////
+
+ /// @name element access
+ /// Access to the JSON value.
+ /// @{
+
+ /*!
+ @brief access specified array element with bounds checking
+
+ Returns a reference to the element at specified location @a idx, with
+ bounds checking.
+
+ @param[in] idx index of the element to access
+
+ @return reference to the element at index @a idx
+
+ @throw std::domain_error if the JSON value is not an array; example:
+ `"cannot use at() with string"`
+ @throw std::out_of_range if the index @a idx is out of range of the array;
+ that is, `idx >= size()`; example: `"array index 7 is out of range"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how array elements can be read and
+ written using `at()`.,at__size_type}
+
+ @since version 1.0.0
+ */
+ reference at(size_type idx)
+ {
+ // at only works for arrays
+ if (is_array())
+ {
+ try
+ {
+ return m_value.array->at(idx);
+ }
+ catch (std::out_of_range&)
+ {
+ // create better exception explanation
+ throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use at() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified array element with bounds checking
+
+ Returns a const reference to the element at specified location @a idx,
+ with bounds checking.
+
+ @param[in] idx index of the element to access
+
+ @return const reference to the element at index @a idx
+
+ @throw std::domain_error if the JSON value is not an array; example:
+ `"cannot use at() with string"`
+ @throw std::out_of_range if the index @a idx is out of range of the array;
+ that is, `idx >= size()`; example: `"array index 7 is out of range"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how array elements can be read using
+ `at()`.,at__size_type_const}
+
+ @since version 1.0.0
+ */
+ const_reference at(size_type idx) const
+ {
+ // at only works for arrays
+ if (is_array())
+ {
+ try
+ {
+ return m_value.array->at(idx);
+ }
+ catch (std::out_of_range&)
+ {
+ // create better exception explanation
+ throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use at() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified object element with bounds checking
+
+ Returns a reference to the element at with specified key @a key, with
+ bounds checking.
+
+ @param[in] key key of the element to access
+
+ @return reference to the element at key @a key
+
+ @throw std::domain_error if the JSON value is not an object; example:
+ `"cannot use at() with boolean"`
+ @throw std::out_of_range if the key @a key is is not stored in the object;
+ that is, `find(key) == end()`; example: `"key "the fast" not found"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read and
+ written using `at()`.,at__object_t_key_type}
+
+ @sa @ref operator[](const typename object_t::key_type&) for unchecked
+ access by reference
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ reference at(const typename object_t::key_type& key)
+ {
+ // at only works for objects
+ if (is_object())
+ {
+ try
+ {
+ return m_value.object->at(key);
+ }
+ catch (std::out_of_range&)
+ {
+ // create better exception explanation
+ throw std::out_of_range("key '" + key + "' not found");
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use at() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified object element with bounds checking
+
+ Returns a const reference to the element at with specified key @a key,
+ with bounds checking.
+
+ @param[in] key key of the element to access
+
+ @return const reference to the element at key @a key
+
+ @throw std::domain_error if the JSON value is not an object; example:
+ `"cannot use at() with boolean"`
+ @throw std::out_of_range if the key @a key is is not stored in the object;
+ that is, `find(key) == end()`; example: `"key "the fast" not found"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read using
+ `at()`.,at__object_t_key_type_const}
+
+ @sa @ref operator[](const typename object_t::key_type&) for unchecked
+ access by reference
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ const_reference at(const typename object_t::key_type& key) const
+ {
+ // at only works for objects
+ if (is_object())
+ {
+ try
+ {
+ return m_value.object->at(key);
+ }
+ catch (std::out_of_range&)
+ {
+ // create better exception explanation
+ throw std::out_of_range("key '" + key + "' not found");
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use at() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified array element
+
+ Returns a reference to the element at specified location @a idx.
+
+ @note If @a idx is beyond the range of the array (i.e., `idx >= size()`),
+ then the array is silently filled up with `null` values to make `idx` a
+ valid reference to the last stored element.
+
+ @param[in] idx index of the element to access
+
+ @return reference to the element at index @a idx
+
+ @throw std::domain_error if JSON is not an array or null; example:
+ `"cannot use operator[] with string"`
+
+ @complexity Constant if @a idx is in the range of the array. Otherwise
+ linear in `idx - size()`.
+
+ @liveexample{The example below shows how array elements can be read and
+ written using `[]` operator. Note the addition of `null`
+ values.,operatorarray__size_type}
+
+ @since version 1.0.0
+ */
+ reference operator[](size_type idx)
+ {
+ // implicitly convert null value to an empty array
+ if (is_null())
+ {
+ m_type = value_t::array;
+ m_value.array = create<array_t>();
+ assert_invariant();
+ }
+
+ // operator[] only works for arrays
+ if (is_array())
+ {
+ // fill up array with null values if given idx is outside range
+ if (idx >= m_value.array->size())
+ {
+ m_value.array->insert(m_value.array->end(),
+ idx - m_value.array->size() + 1,
+ basic_json());
+ }
+
+ return m_value.array->operator[](idx);
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified array element
+
+ Returns a const reference to the element at specified location @a idx.
+
+ @param[in] idx index of the element to access
+
+ @return const reference to the element at index @a idx
+
+ @throw std::domain_error if JSON is not an array; example: `"cannot use
+ operator[] with null"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how array elements can be read using
+ the `[]` operator.,operatorarray__size_type_const}
+
+ @since version 1.0.0
+ */
+ const_reference operator[](size_type idx) const
+ {
+ // const operator[] only works for arrays
+ if (is_array())
+ {
+ return m_value.array->operator[](idx);
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified object element
+
+ Returns a reference to the element at with specified key @a key.
+
+ @note If @a key is not found in the object, then it is silently added to
+ the object and filled with a `null` value to make `key` a valid reference.
+ In case the value was `null` before, it is converted to an object.
+
+ @param[in] key key of the element to access
+
+ @return reference to the element at key @a key
+
+ @throw std::domain_error if JSON is not an object or null; example:
+ `"cannot use operator[] with string"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read and
+ written using the `[]` operator.,operatorarray__key_type}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ reference operator[](const typename object_t::key_type& key)
+ {
+ // implicitly convert null value to an empty object
+ if (is_null())
+ {
+ m_type = value_t::object;
+ m_value.object = create<object_t>();
+ assert_invariant();
+ }
+
+ // operator[] only works for objects
+ if (is_object())
+ {
+ return m_value.object->operator[](key);
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief read-only access specified object element
+
+ Returns a const reference to the element at with specified key @a key. No
+ bounds checking is performed.
+
+ @warning If the element with key @a key does not exist, the behavior is
+ undefined.
+
+ @param[in] key key of the element to access
+
+ @return const reference to the element at key @a key
+
+ @pre The element with key @a key must exist. **This precondition is
+ enforced with an assertion.**
+
+ @throw std::domain_error if JSON is not an object; example: `"cannot use
+ operator[] with null"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read using
+ the `[]` operator.,operatorarray__key_type_const}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ const_reference operator[](const typename object_t::key_type& key) const
+ {
+ // const operator[] only works for objects
+ if (is_object())
+ {
+ assert(m_value.object->find(key) != m_value.object->end());
+ return m_value.object->find(key)->second;
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified object element
+
+ Returns a reference to the element at with specified key @a key.
+
+ @note If @a key is not found in the object, then it is silently added to
+ the object and filled with a `null` value to make `key` a valid reference.
+ In case the value was `null` before, it is converted to an object.
+
+ @param[in] key key of the element to access
+
+ @return reference to the element at key @a key
+
+ @throw std::domain_error if JSON is not an object or null; example:
+ `"cannot use operator[] with string"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read and
+ written using the `[]` operator.,operatorarray__key_type}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ template<typename T, std::size_t n>
+ reference operator[](T * (&key)[n])
+ {
+ return operator[](static_cast<const T>(key));
+ }
+
+ /*!
+ @brief read-only access specified object element
+
+ Returns a const reference to the element at with specified key @a key. No
+ bounds checking is performed.
+
+ @warning If the element with key @a key does not exist, the behavior is
+ undefined.
+
+ @note This function is required for compatibility reasons with Clang.
+
+ @param[in] key key of the element to access
+
+ @return const reference to the element at key @a key
+
+ @throw std::domain_error if JSON is not an object; example: `"cannot use
+ operator[] with null"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read using
+ the `[]` operator.,operatorarray__key_type_const}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.0.0
+ */
+ template<typename T, std::size_t n>
+ const_reference operator[](T * (&key)[n]) const
+ {
+ return operator[](static_cast<const T>(key));
+ }
+
+ /*!
+ @brief access specified object element
+
+ Returns a reference to the element at with specified key @a key.
+
+ @note If @a key is not found in the object, then it is silently added to
+ the object and filled with a `null` value to make `key` a valid reference.
+ In case the value was `null` before, it is converted to an object.
+
+ @param[in] key key of the element to access
+
+ @return reference to the element at key @a key
+
+ @throw std::domain_error if JSON is not an object or null; example:
+ `"cannot use operator[] with string"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read and
+ written using the `[]` operator.,operatorarray__key_type}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.1.0
+ */
+ template<typename T>
+ reference operator[](T* key)
+ {
+ // implicitly convert null to object
+ if (is_null())
+ {
+ m_type = value_t::object;
+ m_value = value_t::object;
+ assert_invariant();
+ }
+
+ // at only works for objects
+ if (is_object())
+ {
+ return m_value.object->operator[](key);
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief read-only access specified object element
+
+ Returns a const reference to the element at with specified key @a key. No
+ bounds checking is performed.
+
+ @warning If the element with key @a key does not exist, the behavior is
+ undefined.
+
+ @param[in] key key of the element to access
+
+ @return const reference to the element at key @a key
+
+ @pre The element with key @a key must exist. **This precondition is
+ enforced with an assertion.**
+
+ @throw std::domain_error if JSON is not an object; example: `"cannot use
+ operator[] with null"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be read using
+ the `[]` operator.,operatorarray__key_type_const}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref value() for access by value with a default value
+
+ @since version 1.1.0
+ */
+ template<typename T>
+ const_reference operator[](T* key) const
+ {
+ // at only works for objects
+ if (is_object())
+ {
+ assert(m_value.object->find(key) != m_value.object->end());
+ return m_value.object->find(key)->second;
+ }
+ else
+ {
+ throw std::domain_error("cannot use operator[] with " + type_name());
+ }
+ }
+
+ /*!
+ @brief access specified object element with default value
+
+ Returns either a copy of an object's element at the specified key @a key
+ or a given default value if no element with key @a key exists.
+
+ The function is basically equivalent to executing
+ @code {.cpp}
+ try {
+ return at(key);
+ } catch(std::out_of_range) {
+ return default_value;
+ }
+ @endcode
+
+ @note Unlike @ref at(const typename object_t::key_type&), this function
+ does not throw if the given key @a key was not found.
+
+ @note Unlike @ref operator[](const typename object_t::key_type& key), this
+ function does not implicitly add an element to the position defined by @a
+ key. This function is furthermore also applicable to const objects.
+
+ @param[in] key key of the element to access
+ @param[in] default_value the value to return if @a key is not found
+
+ @tparam ValueType type compatible to JSON values, for instance `int` for
+ JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
+ JSON arrays. Note the type of the expected value at @a key and the default
+ value @a default_value must be compatible.
+
+ @return copy of the element at key @a key or @a default_value if @a key
+ is not found
+
+ @throw std::domain_error if JSON is not an object; example: `"cannot use
+ value() with null"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be queried
+ with a default value.,basic_json__value}
+
+ @sa @ref at(const typename object_t::key_type&) for access by reference
+ with range checking
+ @sa @ref operator[](const typename object_t::key_type&) for unchecked
+ access by reference
+
+ @since version 1.0.0
+ */
+ template<class ValueType, typename std::enable_if<
+ std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
+ ValueType value(const typename object_t::key_type& key, ValueType default_value) const
+ {
+ // at only works for objects
+ if (is_object())
+ {
+ // if key is found, return value and given default value otherwise
+ const auto it = find(key);
+ if (it != end())
+ {
+ return *it;
+ }
+ else
+ {
+ return default_value;
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use value() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief overload for a default value of type const char*
+ @copydoc basic_json::value(const typename object_t::key_type&, ValueType) const
+ */
+ string_t value(const typename object_t::key_type& key, const char* default_value) const
+ {
+ return value(key, string_t(default_value));
+ }
+
+ /*!
+ @brief access specified object element via JSON Pointer with default value
+
+ Returns either a copy of an object's element at the specified key @a key
+ or a given default value if no element with key @a key exists.
+
+ The function is basically equivalent to executing
+ @code {.cpp}
+ try {
+ return at(ptr);
+ } catch(std::out_of_range) {
+ return default_value;
+ }
+ @endcode
+
+ @note Unlike @ref at(const json_pointer&), this function does not throw
+ if the given key @a key was not found.
+
+ @param[in] ptr a JSON pointer to the element to access
+ @param[in] default_value the value to return if @a ptr found no value
+
+ @tparam ValueType type compatible to JSON values, for instance `int` for
+ JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
+ JSON arrays. Note the type of the expected value at @a key and the default
+ value @a default_value must be compatible.
+
+ @return copy of the element at key @a key or @a default_value if @a key
+ is not found
+
+ @throw std::domain_error if JSON is not an object; example: `"cannot use
+ value() with null"`
+
+ @complexity Logarithmic in the size of the container.
+
+ @liveexample{The example below shows how object elements can be queried
+ with a default value.,basic_json__value_ptr}
+
+ @sa @ref operator[](const json_pointer&) for unchecked access by reference
+
+ @since version 2.0.2
+ */
+ template<class ValueType, typename std::enable_if<
+ std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
+ ValueType value(const json_pointer& ptr, ValueType default_value) const
+ {
+ // at only works for objects
+ if (is_object())
+ {
+ // if pointer resolves a value, return it or use default value
+ try
+ {
+ return ptr.get_checked(this);
+ }
+ catch (std::out_of_range&)
+ {
+ return default_value;
+ }
+ }
+ else
+ {
+ throw std::domain_error("cannot use value() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief overload for a default value of type const char*
+ @copydoc basic_json::value(const json_pointer&, ValueType) const
+ */
+ string_t value(const json_pointer& ptr, const char* default_value) const
+ {
+ return value(ptr, string_t(default_value));
+ }
+
+ /*!
+ @brief access the first element
+
+ Returns a reference to the first element in the container. For a JSON
+ container `c`, the expression `c.front()` is equivalent to `*c.begin()`.
+
+ @return In case of a structured type (array or object), a reference to the
+ first element is returned. In cast of number, string, or boolean values, a
+ reference to the value is returned.
+
+ @complexity Constant.
+
+ @pre The JSON value must not be `null` (would throw `std::out_of_range`)
+ or an empty array or object (undefined behavior, **guarded by
+ assertions**).
+ @post The JSON value remains unchanged.
+
+ @throw std::out_of_range when called on `null` value
+
+ @liveexample{The following code shows an example for `front()`.,front}
+
+ @sa @ref back() -- access the last element
+
+ @since version 1.0.0
+ */
+ reference front()
+ {
+ return *begin();
+ }
+
+ /*!
+ @copydoc basic_json::front()
+ */
+ const_reference front() const
+ {
+ return *cbegin();
+ }
+
+ /*!
+ @brief access the last element
+
+ Returns a reference to the last element in the container. For a JSON
+ container `c`, the expression `c.back()` is equivalent to
+ @code {.cpp}
+ auto tmp = c.end();
+ --tmp;
+ return *tmp;
+ @endcode
+
+ @return In case of a structured type (array or object), a reference to the
+ last element is returned. In cast of number, string, or boolean values, a
+ reference to the value is returned.
+
+ @complexity Constant.
+
+ @pre The JSON value must not be `null` (would throw `std::out_of_range`)
+ or an empty array or object (undefined behavior, **guarded by
+ assertions**).
+ @post The JSON value remains unchanged.
+
+ @throw std::out_of_range when called on `null` value.
+
+ @liveexample{The following code shows an example for `back()`.,back}
+
+ @sa @ref front() -- access the first element
+
+ @since version 1.0.0
+ */
+ reference back()
+ {
+ auto tmp = end();
+ --tmp;
+ return *tmp;
+ }
+
+ /*!
+ @copydoc basic_json::back()
+ */
+ const_reference back() const
+ {
+ auto tmp = cend();
+ --tmp;
+ return *tmp;
+ }
+
+ /*!
+ @brief remove element given an iterator
+
+ Removes the element specified by iterator @a pos. The iterator @a pos must
+ be valid and dereferenceable. Thus the `end()` iterator (which is valid,
+ but is not dereferenceable) cannot be used as a value for @a pos.
+
+ If called on a primitive type other than `null`, the resulting JSON value
+ will be `null`.
+
+ @param[in] pos iterator to the element to remove
+ @return Iterator following the last removed element. If the iterator @a
+ pos refers to the last element, the `end()` iterator is returned.
+
+ @tparam IteratorType an @ref iterator or @ref const_iterator
+
+ @post Invalidates iterators and references at or after the point of the
+ erase, including the `end()` iterator.
+
+ @throw std::domain_error if called on a `null` value; example: `"cannot
+ use erase() with null"`
+ @throw std::domain_error if called on an iterator which does not belong to
+ the current JSON value; example: `"iterator does not fit current value"`
+ @throw std::out_of_range if called on a primitive type with invalid
+ iterator (i.e., any iterator which is not `begin()`); example: `"iterator
+ out of range"`
+
+ @complexity The complexity depends on the type:
+ - objects: amortized constant
+ - arrays: linear in distance between pos and the end of the container
+ - strings: linear in the length of the string
+ - other types: constant
+
+ @liveexample{The example shows the result of `erase()` for different JSON
+ types.,erase__IteratorType}
+
+ @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+ the given range
+ @sa @ref erase(const typename object_t::key_type&) -- removes the element
+ from an object at the given key
+ @sa @ref erase(const size_type) -- removes the element from an array at
+ the given index
+
+ @since version 1.0.0
+ */
+ template<class IteratorType, typename std::enable_if<
+ std::is_same<IteratorType, typename basic_json_t::iterator>::value or
+ std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type
+ = 0>
+ IteratorType erase(IteratorType pos)
+ {
+ // make sure iterator fits the current value
+ if (this != pos.m_object)
+ {
+ throw std::domain_error("iterator does not fit current value");
+ }
+
+ IteratorType result = end();
+
+ switch (m_type)
+ {
+ case value_t::boolean:
+ case value_t::number_float:
+ case value_t::number_integer:
+ case value_t::number_unsigned:
+ case value_t::string:
+ {
+ if (not pos.m_it.primitive_iterator.is_begin())
+ {
+ throw std::out_of_range("iterator out of range");
+ }
+
+ if (is_string())
+ {
+ AllocatorType<string_t> alloc;
+ alloc.destroy(m_value.string);
+ alloc.deallocate(m_value.string, 1);
+ m_value.string = nullptr;
+ }
+
+ m_type = value_t::null;
+ assert_invariant();
+ break;
+ }
+
+ case value_t::object:
+ {
+ result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator);
+ break;
+ }
+
+ case value_t::array:
+ {
+ result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator);
+ break;
+ }
+
+ default:
+ {
+ throw std::domain_error("cannot use erase() with " + type_name());
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief remove elements given an iterator range
+
+ Removes the element specified by the range `[first; last)`. The iterator
+ @a first does not need to be dereferenceable if `first == last`: erasing
+ an empty range is a no-op.
+
+ If called on a primitive type other than `null`, the resulting JSON value
+ will be `null`.
+
+ @param[in] first iterator to the beginning of the range to remove
+ @param[in] last iterator past the end of the range to remove
+ @return Iterator following the last removed element. If the iterator @a
+ second refers to the last element, the `end()` iterator is returned.
+
+ @tparam IteratorType an @ref iterator or @ref const_iterator
+
+ @post Invalidates iterators and references at or after the point of the
+ erase, including the `end()` iterator.
+
+ @throw std::domain_error if called on a `null` value; example: `"cannot
+ use erase() with null"`
+ @throw std::domain_error if called on iterators which does not belong to
+ the current JSON value; example: `"iterators do not fit current value"`
+ @throw std::out_of_range if called on a primitive type with invalid
+ iterators (i.e., if `first != begin()` and `last != end()`); example:
+ `"iterators out of range"`
+
+ @complexity The complexity depends on the type:
+ - objects: `log(size()) + std::distance(first, last)`
+ - arrays: linear in the distance between @a first and @a last, plus linear
+ in the distance between @a last and end of the container
+ - strings: linear in the length of the string
+ - other types: constant
+
+ @liveexample{The example shows the result of `erase()` for different JSON
+ types.,erase__IteratorType_IteratorType}
+
+ @sa @ref erase(IteratorType) -- removes the element at a given position
+ @sa @ref erase(const typename object_t::key_type&) -- removes the element
+ from an object at the given key
+ @sa @ref erase(const size_type) -- removes the element from an array at
+ the given index
+
+ @since version 1.0.0
+ */
+ template<class IteratorType, typename std::enable_if<
+ std::is_same<IteratorType, typename basic_json_t::iterator>::value or
+ std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type
+ = 0>
+ IteratorType erase(IteratorType first, IteratorType last)
+ {
+ // make sure iterator fits the current value
+ if (this != first.m_object or this != last.m_object)
+ {
+ throw std::domain_error("iterators do not fit current value");
+ }
+
+ IteratorType result = end();
+
+ switch (m_type)
+ {
+ case value_t::boolean:
+ case value_t::number_float:
+ case value_t::number_integer:
+ case value_t::number_unsigned:
+ case value_t::string:
+ {
+ if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end())
+ {
+ throw std::out_of_range("iterators out of range");
+ }
+
+ if (is_string())
+ {
+ AllocatorType<string_t> alloc;
+ alloc.destroy(m_value.string);
+ alloc.deallocate(m_value.string, 1);
+ m_value.string = nullptr;
+ }
+
+ m_type = value_t::null;
+ assert_invariant();
+ break;
+ }
+
+ case value_t::object:
+ {
+ result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator,
+ last.m_it.object_iterator);
+ break;
+ }
+
+ case value_t::array:
+ {
+ result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator,
+ last.m_it.array_iterator);
+ break;
+ }
+
+ default:
+ {
+ throw std::domain_error("cannot use erase() with " + type_name());
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief remove element from a JSON object given a key
+
+ Removes elements from a JSON object with the key value @a key.
+
+ @param[in] key value of the elements to remove
+
+ @return Number of elements removed. If @a ObjectType is the default
+ `std::map` type, the return value will always be `0` (@a key was not
+ found) or `1` (@a key was found).
+
+ @post References and iterators to the erased elements are invalidated.
+ Other references and iterators are not affected.
+
+ @throw std::domain_error when called on a type other than JSON object;
+ example: `"cannot use erase() with null"`
+
+ @complexity `log(size()) + count(key)`
+
+ @liveexample{The example shows the effect of `erase()`.,erase__key_type}
+
+ @sa @ref erase(IteratorType) -- removes the element at a given position
+ @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+ the given range
+ @sa @ref erase(const size_type) -- removes the element from an array at
+ the given index
+
+ @since version 1.0.0
+ */
+ size_type erase(const typename object_t::key_type& key)
+ {
+ // this erase only works for objects
+ if (is_object())
+ {
+ return m_value.object->erase(key);
+ }
+ else
+ {
+ throw std::domain_error("cannot use erase() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief remove element from a JSON array given an index
+
+ Removes element from a JSON array at the index @a idx.
+
+ @param[in] idx index of the element to remove
+
+ @throw std::domain_error when called on a type other than JSON array;
+ example: `"cannot use erase() with null"`
+ @throw std::out_of_range when `idx >= size()`; example: `"array index 17
+ is out of range"`
+
+ @complexity Linear in distance between @a idx and the end of the container.
+
+ @liveexample{The example shows the effect of `erase()`.,erase__size_type}
+
+ @sa @ref erase(IteratorType) -- removes the element at a given position
+ @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+ the given range
+ @sa @ref erase(const typename object_t::key_type&) -- removes the element
+ from an object at the given key
+
+ @since version 1.0.0
+ */
+ void erase(const size_type idx)
+ {
+ // this erase only works for arrays
+ if (is_array())
+ {
+ if (idx >= size())
+ {
+ throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
+ }
+
+ m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx));
+ }
+ else
+ {
+ throw std::domain_error("cannot use erase() with " + type_name());
+ }
+ }
+
+ /// @}
+
+
+ ////////////
+ // lookup //
+ ////////////
+
+ /// @name lookup
+ /// @{
+
+ /*!
+ @brief find an element in a JSON object
+
+ Finds an element in a JSON object with key equivalent to @a key. If the
+ element is not found or the JSON value is not an object, end() is
+ returned.
+
+ @param[in] key key value of the element to search for
+
+ @return Iterator to an element with key equivalent to @a key. If no such
+ element is found, past-the-end (see end()) iterator is returned.
+
+ @complexity Logarithmic in the size of the JSON object.
+
+ @liveexample{The example shows how `find()` is used.,find__key_type}
+
+ @since version 1.0.0
+ */
+ iterator find(typename object_t::key_type key)
+ {
+ auto result = end();
+
+ if (is_object())
+ {
+ result.m_it.object_iterator = m_value.object->find(key);
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief find an element in a JSON object
+ @copydoc find(typename object_t::key_type)
+ */
+ const_iterator find(typename object_t::key_type key) const
+ {
+ auto result = cend();
+
+ if (is_object())
+ {
+ result.m_it.object_iterator = m_value.object->find(key);
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief returns the number of occurrences of a key in a JSON object
+
+ Returns the number of elements with key @a key. If ObjectType is the
+ default `std::map` type, the return value will always be `0` (@a key was
+ not found) or `1` (@a key was found).
+
+ @param[in] key key value of the element to count
+
+ @return Number of elements with key @a key. If the JSON value is not an
+ object, the return value will be `0`.
+
+ @complexity Logarithmic in the size of the JSON object.
+
+ @liveexample{The example shows how `count()` is used.,count}
+
+ @since version 1.0.0
+ */
+ size_type count(typename object_t::key_type key) const
+ {
+ // return 0 for all nonobject types
+ return is_object() ? m_value.object->count(key) : 0;
+ }
+
+ /// @}
+
+
+ ///////////////
+ // iterators //
+ ///////////////
+
+ /// @name iterators
+ /// @{
+
+ /*!
+ @brief returns an iterator to the first element
+
+ Returns an iterator to the first element.
+
+ @image html range-begin-end.svg "Illustration from cppreference.com"
+
+ @return iterator to the first element
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+
+ @liveexample{The following code shows an example for `begin()`.,begin}
+
+ @sa @ref cbegin() -- returns a const iterator to the beginning
+ @sa @ref end() -- returns an iterator to the end
+ @sa @ref cend() -- returns a const iterator to the end
+
+ @since version 1.0.0
+ */
+ iterator begin() noexcept
+ {
+ iterator result(this);
+ result.set_begin();
+ return result;
+ }
+
+ /*!
+ @copydoc basic_json::cbegin()
+ */
+ const_iterator begin() const noexcept
+ {
+ return cbegin();
+ }
+
+ /*!
+ @brief returns a const iterator to the first element
+
+ Returns a const iterator to the first element.
+
+ @image html range-begin-end.svg "Illustration from cppreference.com"
+
+ @return const iterator to the first element
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `const_cast<const basic_json&>(*this).begin()`.
+
+ @liveexample{The following code shows an example for `cbegin()`.,cbegin}
+
+ @sa @ref begin() -- returns an iterator to the beginning
+ @sa @ref end() -- returns an iterator to the end
+ @sa @ref cend() -- returns a const iterator to the end
+
+ @since version 1.0.0
+ */
+ const_iterator cbegin() const noexcept
+ {
+ const_iterator result(this);
+ result.set_begin();
+ return result;
+ }
+
+ /*!
+ @brief returns an iterator to one past the last element
+
+ Returns an iterator to one past the last element.
+
+ @image html range-begin-end.svg "Illustration from cppreference.com"
+
+ @return iterator one past the last element
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+
+ @liveexample{The following code shows an example for `end()`.,end}
+
+ @sa @ref cend() -- returns a const iterator to the end
+ @sa @ref begin() -- returns an iterator to the beginning
+ @sa @ref cbegin() -- returns a const iterator to the beginning
+
+ @since version 1.0.0
+ */
+ iterator end() noexcept
+ {
+ iterator result(this);
+ result.set_end();
+ return result;
+ }
+
+ /*!
+ @copydoc basic_json::cend()
+ */
+ const_iterator end() const noexcept
+ {
+ return cend();
+ }
+
+ /*!
+ @brief returns a const iterator to one past the last element
+
+ Returns a const iterator to one past the last element.
+
+ @image html range-begin-end.svg "Illustration from cppreference.com"
+
+ @return const iterator one past the last element
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `const_cast<const basic_json&>(*this).end()`.
+
+ @liveexample{The following code shows an example for `cend()`.,cend}
+
+ @sa @ref end() -- returns an iterator to the end
+ @sa @ref begin() -- returns an iterator to the beginning
+ @sa @ref cbegin() -- returns a const iterator to the beginning
+
+ @since version 1.0.0
+ */
+ const_iterator cend() const noexcept
+ {
+ const_iterator result(this);
+ result.set_end();
+ return result;
+ }
+
+ /*!
+ @brief returns an iterator to the reverse-beginning
+
+ Returns an iterator to the reverse-beginning; that is, the last element.
+
+ @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `reverse_iterator(end())`.
+
+ @liveexample{The following code shows an example for `rbegin()`.,rbegin}
+
+ @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+ @sa @ref rend() -- returns a reverse iterator to the end
+ @sa @ref crend() -- returns a const reverse iterator to the end
+
+ @since version 1.0.0
+ */
+ reverse_iterator rbegin() noexcept
+ {
+ return reverse_iterator(end());
+ }
+
+ /*!
+ @copydoc basic_json::crbegin()
+ */
+ const_reverse_iterator rbegin() const noexcept
+ {
+ return crbegin();
+ }
+
+ /*!
+ @brief returns an iterator to the reverse-end
+
+ Returns an iterator to the reverse-end; that is, one before the first
+ element.
+
+ @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `reverse_iterator(begin())`.
+
+ @liveexample{The following code shows an example for `rend()`.,rend}
+
+ @sa @ref crend() -- returns a const reverse iterator to the end
+ @sa @ref rbegin() -- returns a reverse iterator to the beginning
+ @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+
+ @since version 1.0.0
+ */
+ reverse_iterator rend() noexcept
+ {
+ return reverse_iterator(begin());
+ }
+
+ /*!
+ @copydoc basic_json::crend()
+ */
+ const_reverse_iterator rend() const noexcept
+ {
+ return crend();
+ }
+
+ /*!
+ @brief returns a const reverse iterator to the last element
+
+ Returns a const iterator to the reverse-beginning; that is, the last
+ element.
+
+ @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `const_cast<const basic_json&>(*this).rbegin()`.
+
+ @liveexample{The following code shows an example for `crbegin()`.,crbegin}
+
+ @sa @ref rbegin() -- returns a reverse iterator to the beginning
+ @sa @ref rend() -- returns a reverse iterator to the end
+ @sa @ref crend() -- returns a const reverse iterator to the end
+
+ @since version 1.0.0
+ */
+ const_reverse_iterator crbegin() const noexcept
+ {
+ return const_reverse_iterator(cend());
+ }
+
+ /*!
+ @brief returns a const reverse iterator to one before the first
+
+ Returns a const reverse iterator to the reverse-end; that is, one before
+ the first element.
+
+ @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+ @complexity Constant.
+
+ @requirement This function helps `basic_json` satisfying the
+ [ReversibleContainer](http://en.cppreference.com/w/cpp/concept/ReversibleContainer)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `const_cast<const basic_json&>(*this).rend()`.
+
+ @liveexample{The following code shows an example for `crend()`.,crend}
+
+ @sa @ref rend() -- returns a reverse iterator to the end
+ @sa @ref rbegin() -- returns a reverse iterator to the beginning
+ @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+
+ @since version 1.0.0
+ */
+ const_reverse_iterator crend() const noexcept
+ {
+ return const_reverse_iterator(cbegin());
+ }
+
+ private:
+ // forward declaration
+ template<typename IteratorType> class iteration_proxy;
+
+ public:
+ /*!
+ @brief wrapper to access iterator member functions in range-based for
+
+ This function allows to access @ref iterator::key() and @ref
+ iterator::value() during range-based for loops. In these loops, a
+ reference to the JSON values is returned, so there is no access to the
+ underlying iterator.
+
+ @note The name of this function is not yet final and may change in the
+ future.
+ */
+ static iteration_proxy<iterator> iterator_wrapper(reference cont)
+ {
+ return iteration_proxy<iterator>(cont);
+ }
+
+ /*!
+ @copydoc iterator_wrapper(reference)
+ */
+ static iteration_proxy<const_iterator> iterator_wrapper(const_reference cont)
+ {
+ return iteration_proxy<const_iterator>(cont);
+ }
+
+ /// @}
+
+
+ //////////////
+ // capacity //
+ //////////////
+
+ /// @name capacity
+ /// @{
+
+ /*!
+ @brief checks whether the container is empty
+
+ Checks if a JSON value has no elements.
+
+ @return The return value depends on the different types and is
+ defined as follows:
+ Value type | return value
+ ----------- | -------------
+ null | `true`
+ boolean | `false`
+ string | `false`
+ number | `false`
+ object | result of function `object_t::empty()`
+ array | result of function `array_t::empty()`
+
+ @note This function does not return whether a string stored as JSON value
+ is empty - it returns whether the JSON container itself is empty which is
+ false in the case of a string.
+
+ @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+ the Container concept; that is, their `empty()` functions have constant
+ complexity.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `begin() == end()`.
+
+ @liveexample{The following code uses `empty()` to check if a JSON
+ object contains any elements.,empty}
+
+ @sa @ref size() -- returns the number of elements
+
+ @since version 1.0.0
+ */
+ bool empty() const noexcept
+ {
+ switch (m_type)
+ {
+ case value_t::null:
+ {
+ // null values are empty
+ return true;
+ }
+
+ case value_t::array:
+ {
+ // delegate call to array_t::empty()
+ return m_value.array->empty();
+ }
+
+ case value_t::object:
+ {
+ // delegate call to object_t::empty()
+ return m_value.object->empty();
+ }
+
+ default:
+ {
+ // all other types are nonempty
+ return false;
+ }
+ }
+ }
+
+ /*!
+ @brief returns the number of elements
+
+ Returns the number of elements in a JSON value.
+
+ @return The return value depends on the different types and is
+ defined as follows:
+ Value type | return value
+ ----------- | -------------
+ null | `0`
+ boolean | `1`
+ string | `1`
+ number | `1`
+ object | result of function object_t::size()
+ array | result of function array_t::size()
+
+ @note This function does not return the length of a string stored as JSON
+ value - it returns the number of elements in the JSON value which is 1 in
+ the case of a string.
+
+ @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+ the Container concept; that is, their size() functions have constant
+ complexity.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of `std::distance(begin(), end())`.
+
+ @liveexample{The following code calls `size()` on the different value
+ types.,size}
+
+ @sa @ref empty() -- checks whether the container is empty
+ @sa @ref max_size() -- returns the maximal number of elements
+
+ @since version 1.0.0
+ */
+ size_type size() const noexcept
+ {
+ switch (m_type)
+ {
+ case value_t::null:
+ {
+ // null values are empty
+ return 0;
+ }
+
+ case value_t::array:
+ {
+ // delegate call to array_t::size()
+ return m_value.array->size();
+ }
+
+ case value_t::object:
+ {
+ // delegate call to object_t::size()
+ return m_value.object->size();
+ }
+
+ default:
+ {
+ // all other types have size 1
+ return 1;
+ }
+ }
+ }
+
+ /*!
+ @brief returns the maximum possible number of elements
+
+ Returns the maximum number of elements a JSON value is able to hold due to
+ system or library implementation limitations, i.e. `std::distance(begin(),
+ end())` for the JSON value.
+
+ @return The return value depends on the different types and is
+ defined as follows:
+ Value type | return value
+ ----------- | -------------
+ null | `0` (same as `size()`)
+ boolean | `1` (same as `size()`)
+ string | `1` (same as `size()`)
+ number | `1` (same as `size()`)
+ object | result of function `object_t::max_size()`
+ array | result of function `array_t::max_size()`
+
+ @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+ the Container concept; that is, their `max_size()` functions have constant
+ complexity.
+
+ @requirement This function helps `basic_json` satisfying the
+ [Container](http://en.cppreference.com/w/cpp/concept/Container)
+ requirements:
+ - The complexity is constant.
+ - Has the semantics of returning `b.size()` where `b` is the largest
+ possible JSON value.
+
+ @liveexample{The following code calls `max_size()` on the different value
+ types. Note the output is implementation specific.,max_size}
+
+ @sa @ref size() -- returns the number of elements
+
+ @since version 1.0.0
+ */
+ size_type max_size() const noexcept
+ {
+ switch (m_type)
+ {
+ case value_t::array:
+ {
+ // delegate call to array_t::max_size()
+ return m_value.array->max_size();
+ }
+
+ case value_t::object:
+ {
+ // delegate call to object_t::max_size()
+ return m_value.object->max_size();
+ }
+
+ default:
+ {
+ // all other types have max_size() == size()
+ return size();
+ }
+ }
+ }
+
+ /// @}
+
+
+ ///////////////
+ // modifiers //
+ ///////////////
+
+ /// @name modifiers
+ /// @{
+
+ /*!
+ @brief clears the contents
+
+ Clears the content of a JSON value and resets it to the default value as
+ if @ref basic_json(value_t) would have been called:
+
+ Value type | initial value
+ ----------- | -------------
+ null | `null`
+ boolean | `false`
+ string | `""`
+ number | `0`
+ object | `{}`
+ array | `[]`
+
+ @note Floating-point numbers are set to `0.0` which will be serialized to
+ `0`. The vale type remains @ref number_float_t.
+
+ @complexity Linear in the size of the JSON value.
+
+ @liveexample{The example below shows the effect of `clear()` to different
+ JSON types.,clear}
+
+ @since version 1.0.0
+ */
+ void clear() noexcept
+ {
+ switch (m_type)
+ {
+ case value_t::number_integer:
+ {
+ m_value.number_integer = 0;
+ break;
+ }
+
+ case value_t::number_unsigned:
+ {
+ m_value.number_unsigned = 0;
+ break;
+ }
+
+ case value_t::number_float:
+ {
+ m_value.number_float = 0.0;
+ break;
+ }
+
+ case value_t::boolean:
+ {
+ m_value.boolean = false;
+ break;
+ }
+
+ case value_t::string:
+ {
+ m_value.string->clear();
+ break;
+ }
+
+ case value_t::array:
+ {
+ m_value.array->clear();
+ break;
+ }
+
+ case value_t::object:
+ {
+ m_value.object->clear();
+ break;
+ }
+
+ default:
+ {
+ break;
+ }
+ }
+ }
+
+ /*!
+ @brief add an object to an array
+
+ Appends the given element @a val to the end of the JSON value. If the
+ function is called on a JSON null value, an empty array is created before
+ appending @a val.
+
+ @param[in] val the value to add to the JSON array
+
+ @throw std::domain_error when called on a type other than JSON array or
+ null; example: `"cannot use push_back() with number"`
+
+ @complexity Amortized constant.
+
+ @liveexample{The example shows how `push_back()` and `+=` can be used to
+ add elements to a JSON array. Note how the `null` value was silently
+ converted to a JSON array.,push_back}
+
+ @since version 1.0.0
+ */
+ void push_back(basic_json&& val)
+ {
+ // push_back only works for null objects or arrays
+ if (not(is_null() or is_array()))
+ {
+ throw std::domain_error("cannot use push_back() with " + type_name());
+ }
+
+ // transform null object into an array
+ if (is_null())
+ {
+ m_type = value_t::array;
+ m_value = value_t::array;
+ assert_invariant();
+ }
+
+ // add element to array (move semantics)
+ m_value.array->push_back(std::move(val));
+ // invalidate object
+ val.m_type = value_t::null;
+ }
+
+ /*!
+ @brief add an object to an array
+ @copydoc push_back(basic_json&&)
+ */
+ reference operator+=(basic_json&& val)
+ {
+ push_back(std::move(val));
+ return *this;
+ }
+
+ /*!
+ @brief add an object to an array
+ @copydoc push_back(basic_json&&)
+ */
+ void push_back(const basic_json& val)
+ {
+ // push_back only works for null objects or arrays
+ if (not(is_null() or is_array()))
+ {
+ throw std::domain_error("cannot use push_back() with " + type_name());
+ }
+
+ // transform null object into an array
+ if (is_null())
+ {
+ m_type = value_t::array;
+ m_value = value_t::array;
+ assert_invariant();
+ }
+
+ // add element to array
+ m_value.array->push_back(val);
+ }
+
+ /*!
+ @brief add an object to an array
+ @copydoc push_back(basic_json&&)
+ */
+ reference operator+=(const basic_json& val)
+ {
+ push_back(val);
+ return *this;
+ }
+
+ /*!
+ @brief add an object to an object
+
+ Inserts the given element @a val to the JSON object. If the function is
+ called on a JSON null value, an empty object is created before inserting
+ @a val.
+
+ @param[in] val the value to add to the JSON object
+
+ @throw std::domain_error when called on a type other than JSON object or
+ null; example: `"cannot use push_back() with number"`
+
+ @complexity Logarithmic in the size of the container, O(log(`size()`)).
+
+ @liveexample{The example shows how `push_back()` and `+=` can be used to
+ add elements to a JSON object. Note how the `null` value was silently
+ converted to a JSON object.,push_back__object_t__value}
+
+ @since version 1.0.0
+ */
+ void push_back(const typename object_t::value_type& val)
+ {
+ // push_back only works for null objects or objects
+ if (not(is_null() or is_object()))
+ {
+ throw std::domain_error("cannot use push_back() with " + type_name());
+ }
+
+ // transform null object into an object
+ if (is_null())
+ {
+ m_type = value_t::object;
+ m_value = value_t::object;
+ assert_invariant();
+ }
+
+ // add element to array
+ m_value.object->insert(val);
+ }
+
+ /*!
+ @brief add an object to an object
+ @copydoc push_back(const typename object_t::value_type&)
+ */
+ reference operator+=(const typename object_t::value_type& val)
+ {
+ push_back(val);
+ return *this;
+ }
+
+ /*!
+ @brief add an object to an object
+
+ This function allows to use `push_back` with an initializer list. In case
+
+ 1. the current value is an object,
+ 2. the initializer list @a init contains only two elements, and
+ 3. the first element of @a init is a string,
+
+ @a init is converted into an object element and added using
+ @ref push_back(const typename object_t::value_type&). Otherwise, @a init
+ is converted to a JSON value and added using @ref push_back(basic_json&&).
+
+ @param init an initializer list
+
+ @complexity Linear in the size of the initializer list @a init.
+
+ @note This function is required to resolve an ambiguous overload error,
+ because pairs like `{"key", "value"}` can be both interpreted as
+ `object_t::value_type` or `std::initializer_list<basic_json>`, see
+ https://github.com/nlohmann/json/issues/235 for more information.
+
+ @liveexample{The example shows how initializer lists are treated as
+ objects when possible.,push_back__initializer_list}
+ */
+ void push_back(std::initializer_list<basic_json> init)
+ {
+ if (is_object() and init.size() == 2 and init.begin()->is_string())
+ {
+ const string_t key = *init.begin();
+ push_back(typename object_t::value_type(key, *(init.begin() + 1)));
+ }
+ else
+ {
+ push_back(basic_json(init));
+ }
+ }
+
+ /*!
+ @brief add an object to an object
+ @copydoc push_back(std::initializer_list<basic_json>)
+ */
+ reference operator+=(std::initializer_list<basic_json> init)
+ {
+ push_back(init);
+ return *this;
+ }
+
+ /*!
+ @brief inserts element
+
+ Inserts element @a val before iterator @a pos.
+
+ @param[in] pos iterator before which the content will be inserted; may be
+ the end() iterator
+ @param[in] val element to insert
+ @return iterator pointing to the inserted @a val.
+
+ @throw std::domain_error if called on JSON values other than arrays;
+ example: `"cannot use insert() with string"`
+ @throw std::domain_error if @a pos is not an iterator of *this; example:
+ `"iterator does not fit current value"`
+
+ @complexity Constant plus linear in the distance between pos and end of the
+ container.
+
+ @liveexample{The example shows how `insert()` is used.,insert}
+
+ @since version 1.0.0
+ */
+ iterator insert(const_iterator pos, const basic_json& val)
+ {
+ // insert only works for arrays
+ if (is_array())
+ {
+ // check if iterator pos fits to this JSON value
+ if (pos.m_object != this)
+ {
+ throw std::domain_error("iterator does not fit current value");
+ }
+
+ // insert to array and return iterator
+ iterator result(this);
+ result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, val);
+ return result;
+ }
+ else
+ {
+ throw std::domain_error("cannot use insert() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief inserts element
+ @copydoc insert(const_iterator, const basic_json&)
+ */
+ iterator insert(const_iterator pos, basic_json&& val)
+ {
+ return insert(pos, val);
+ }
+
+ /*!
+ @brief inserts elements
+
+ Inserts @a cnt copies of @a val before iterator @a pos.
+
+ @param[in] pos iterator before which the content will be inserted; may be
+ the end() iterator
+ @param[in] cnt number of copies of @a val to insert
+ @param[in] val element to insert
+ @return iterator pointing to the first element inserted, or @a pos if
+ `cnt==0`
+
+ @throw std::domain_error if called on JSON values other than arrays;
+ example: `"cannot use insert() with string"`
+ @throw std::domain_error if @a pos is not an iterator of *this; example:
+ `"iterator does not fit current value"`
+
+ @complexity Linear in @a cnt plus linear in the distance between @a pos
+ and end of the container.
+
+ @liveexample{The example shows how `insert()` is used.,insert__count}
+
+ @since version 1.0.0
+ */
+ iterator insert(const_iterator pos, size_type cnt, const basic_json& val)
+ {
+ // insert only works for arrays
+ if (is_array())
+ {
+ // check if iterator pos fits to this JSON value
+ if (pos.m_object != this)
+ {
+ throw std::domain_error("iterator does not fit current value");
+ }
+
+ // insert to array and return iterator
+ iterator result(this);
+ result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val);
+ return result;
+ }
+ else
+ {
+ throw std::domain_error("cannot use insert() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief inserts elements
+
+ Inserts elements from range `[first, last)` before iterator @a pos.
+
+ @param[in] pos iterator before which the content will be inserted; may be
+ the end() iterator
+ @param[in] first begin of the range of elements to insert
+ @param[in] last end of the range of elements to insert
+
+ @throw std::domain_error if called on JSON values other than arrays;
+ example: `"cannot use insert() with string"`
+ @throw std::domain_error if @a pos is not an iterator of *this; example:
+ `"iterator does not fit current value"`
+ @throw std::domain_error if @a first and @a last do not belong to the same
+ JSON value; example: `"iterators do not fit"`
+ @throw std::domain_error if @a first or @a last are iterators into
+ container for which insert is called; example: `"passed iterators may not
+ belong to container"`
+
+ @return iterator pointing to the first element inserted, or @a pos if
+ `first==last`
+
+ @complexity Linear in `std::distance(first, last)` plus linear in the
+ distance between @a pos and end of the container.
+
+ @liveexample{The example shows how `insert()` is used.,insert__range}
+
+ @since version 1.0.0
+ */
+ iterator insert(const_iterator pos, const_iterator first, const_iterator last)
+ {
+ // insert only works for arrays
+ if (not is_array())
+ {
+ throw std::domain_error("cannot use insert() with " + type_name());
+ }
+
+ // check if iterator pos fits to this JSON value
+ if (pos.m_object != this)
+ {
+ throw std::domain_error("iterator does not fit current value");
+ }
+
+ // check if range iterators belong to the same JSON object
+ if (first.m_object != last.m_object)
+ {
+ throw std::domain_error("iterators do not fit");
+ }
+
+ if (first.m_object == this or last.m_object == this)
+ {
+ throw std::domain_error("passed iterators may not belong to container");
+ }
+
+ // insert to array and return iterator
+ iterator result(this);
+ result.m_it.array_iterator = m_value.array->insert(
+ pos.m_it.array_iterator,
+ first.m_it.array_iterator,
+ last.m_it.array_iterator);
+ return result;
+ }
+
+ /*!
+ @brief inserts elements
+
+ Inserts elements from initializer list @a ilist before iterator @a pos.
+
+ @param[in] pos iterator before which the content will be inserted; may be
+ the end() iterator
+ @param[in] ilist initializer list to insert the values from
+
+ @throw std::domain_error if called on JSON values other than arrays;
+ example: `"cannot use insert() with string"`
+ @throw std::domain_error if @a pos is not an iterator of *this; example:
+ `"iterator does not fit current value"`
+
+ @return iterator pointing to the first element inserted, or @a pos if
+ `ilist` is empty
+
+ @complexity Linear in `ilist.size()` plus linear in the distance between
+ @a pos and end of the container.
+
+ @liveexample{The example shows how `insert()` is used.,insert__ilist}
+
+ @since version 1.0.0
+ */
+ iterator insert(const_iterator pos, std::initializer_list<basic_json> ilist)
+ {
+ // insert only works for arrays
+ if (not is_array())
+ {
+ throw std::domain_error("cannot use insert() with " + type_name());
+ }
+
+ // check if iterator pos fits to this JSON value
+ if (pos.m_object != this)
+ {
+ throw std::domain_error("iterator does not fit current value");
+ }
+
+ // insert to array and return iterator
+ iterator result(this);
+ result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, ilist);
+ return result;
+ }
+
+ /*!
+ @brief exchanges the values
+
+ Exchanges the contents of the JSON value with those of @a other. Does not
+ invoke any move, copy, or swap operations on individual elements. All
+ iterators and references remain valid. The past-the-end iterator is
+ invalidated.
+
+ @param[in,out] other JSON value to exchange the contents with
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how JSON values can be swapped with
+ `swap()`.,swap__reference}
+
+ @since version 1.0.0
+ */
+ void swap(reference other) noexcept (
+ std::is_nothrow_move_constructible<value_t>::value and
+ std::is_nothrow_move_assignable<value_t>::value and
+ std::is_nothrow_move_constructible<json_value>::value and
+ std::is_nothrow_move_assignable<json_value>::value
+ )
+ {
+ std::swap(m_type, other.m_type);
+ std::swap(m_value, other.m_value);
+ assert_invariant();
+ }
+
+ /*!
+ @brief exchanges the values
+
+ Exchanges the contents of a JSON array with those of @a other. Does not
+ invoke any move, copy, or swap operations on individual elements. All
+ iterators and references remain valid. The past-the-end iterator is
+ invalidated.
+
+ @param[in,out] other array to exchange the contents with
+
+ @throw std::domain_error when JSON value is not an array; example: `"cannot
+ use swap() with string"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how arrays can be swapped with
+ `swap()`.,swap__array_t}
+
+ @since version 1.0.0
+ */
+ void swap(array_t& other)
+ {
+ // swap only works for arrays
+ if (is_array())
+ {
+ std::swap(*(m_value.array), other);
+ }
+ else
+ {
+ throw std::domain_error("cannot use swap() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief exchanges the values
+
+ Exchanges the contents of a JSON object with those of @a other. Does not
+ invoke any move, copy, or swap operations on individual elements. All
+ iterators and references remain valid. The past-the-end iterator is
+ invalidated.
+
+ @param[in,out] other object to exchange the contents with
+
+ @throw std::domain_error when JSON value is not an object; example:
+ `"cannot use swap() with string"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how objects can be swapped with
+ `swap()`.,swap__object_t}
+
+ @since version 1.0.0
+ */
+ void swap(object_t& other)
+ {
+ // swap only works for objects
+ if (is_object())
+ {
+ std::swap(*(m_value.object), other);
+ }
+ else
+ {
+ throw std::domain_error("cannot use swap() with " + type_name());
+ }
+ }
+
+ /*!
+ @brief exchanges the values
+
+ Exchanges the contents of a JSON string with those of @a other. Does not
+ invoke any move, copy, or swap operations on individual elements. All
+ iterators and references remain valid. The past-the-end iterator is
+ invalidated.
+
+ @param[in,out] other string to exchange the contents with
+
+ @throw std::domain_error when JSON value is not a string; example: `"cannot
+ use swap() with boolean"`
+
+ @complexity Constant.
+
+ @liveexample{The example below shows how strings can be swapped with
+ `swap()`.,swap__string_t}
+
+ @since version 1.0.0
+ */
+ void swap(string_t& other)
+ {
+ // swap only works for strings
+ if (is_string())
+ {
+ std::swap(*(m_value.string), other);
+ }
+ else
+ {
+ throw std::domain_error("cannot use swap() with " + type_name());
+ }
+ }
+
+ /// @}
+
+
+ //////////////////////////////////////////
+ // lexicographical comparison operators //
+ //////////////////////////////////////////
+
+ /// @name lexicographical comparison operators
+ /// @{
+
+ private:
+ /*!
+ @brief comparison operator for JSON types
+
+ Returns an ordering that is similar to Python:
+ - order: null < boolean < number < object < array < string
+ - furthermore, each type is not smaller than itself
+
+ @since version 1.0.0
+ */
+ friend bool operator<(const value_t lhs, const value_t rhs) noexcept
+ {
+ static constexpr std::array<uint8_t, 8> order = {{
+ 0, // null
+ 3, // object
+ 4, // array
+ 5, // string
+ 1, // boolean
+ 2, // integer
+ 2, // unsigned
+ 2, // float
+ }
+ };
+
+ // discarded values are not comparable
+ if (lhs == value_t::discarded or rhs == value_t::discarded)
+ {
+ return false;
+ }
+
+ return order[static_cast<std::size_t>(lhs)] < order[static_cast<std::size_t>(rhs)];
+ }
+
+ public:
+ /*!
+ @brief comparison: equal
+
+ Compares two JSON values for equality according to the following rules:
+ - Two JSON values are equal if (1) they are from the same type and (2)
+ their stored values are the same.
+ - Integer and floating-point numbers are automatically converted before
+ comparison. Floating-point numbers are compared indirectly: two
+ floating-point numbers `f1` and `f2` are considered equal if neither
+ `f1 > f2` nor `f2 > f1` holds.
+ - Two JSON null values are equal.
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether the values @a lhs and @a rhs are equal
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__equal}
+
+ @since version 1.0.0
+ */
+ friend bool operator==(const_reference lhs, const_reference rhs) noexcept
+ {
+ const auto lhs_type = lhs.type();
+ const auto rhs_type = rhs.type();
+
+ if (lhs_type == rhs_type)
+ {
+ switch (lhs_type)
+ {
+ case value_t::array:
+ {
+ return *lhs.m_value.array == *rhs.m_value.array;
+ }
+ case value_t::object:
+ {
+ return *lhs.m_value.object == *rhs.m_value.object;
+ }
+ case value_t::null:
+ {
+ return true;
+ }
+ case value_t::string:
+ {
+ return *lhs.m_value.string == *rhs.m_value.string;
+ }
+ case value_t::boolean:
+ {
+ return lhs.m_value.boolean == rhs.m_value.boolean;
+ }
+ case value_t::number_integer:
+ {
+ return lhs.m_value.number_integer == rhs.m_value.number_integer;
+ }
+ case value_t::number_unsigned:
+ {
+ return lhs.m_value.number_unsigned == rhs.m_value.number_unsigned;
+ }
+ case value_t::number_float:
+ {
+ return lhs.m_value.number_float == rhs.m_value.number_float;
+ }
+ default:
+ {
+ return false;
+ }
+ }
+ }
+ else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float)
+ {
+ return static_cast<number_float_t>(lhs.m_value.number_integer) == rhs.m_value.number_float;
+ }
+ else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer)
+ {
+ return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_integer);
+ }
+ else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float)
+ {
+ return static_cast<number_float_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_float;
+ }
+ else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned)
+ {
+ return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_unsigned);
+ }
+ else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer)
+ {
+ return static_cast<number_integer_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_integer;
+ }
+ else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned)
+ {
+ return lhs.m_value.number_integer == static_cast<number_integer_t>(rhs.m_value.number_unsigned);
+ }
+
+ return false;
+ }
+
+ /*!
+ @brief comparison: equal
+
+ The functions compares the given JSON value against a null pointer. As the
+ null pointer can be used to initialize a JSON value to null, a comparison
+ of JSON value @a v with a null pointer should be equivalent to call
+ `v.is_null()`.
+
+ @param[in] v JSON value to consider
+ @return whether @a v is null
+
+ @complexity Constant.
+
+ @liveexample{The example compares several JSON types to the null pointer.
+ ,operator__equal__nullptr_t}
+
+ @since version 1.0.0
+ */
+ friend bool operator==(const_reference v, std::nullptr_t) noexcept
+ {
+ return v.is_null();
+ }
+
+ /*!
+ @brief comparison: equal
+ @copydoc operator==(const_reference, std::nullptr_t)
+ */
+ friend bool operator==(std::nullptr_t, const_reference v) noexcept
+ {
+ return v.is_null();
+ }
+
+ /*!
+ @brief comparison: not equal
+
+ Compares two JSON values for inequality by calculating `not (lhs == rhs)`.
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether the values @a lhs and @a rhs are not equal
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__notequal}
+
+ @since version 1.0.0
+ */
+ friend bool operator!=(const_reference lhs, const_reference rhs) noexcept
+ {
+ return not (lhs == rhs);
+ }
+
+ /*!
+ @brief comparison: not equal
+
+ The functions compares the given JSON value against a null pointer. As the
+ null pointer can be used to initialize a JSON value to null, a comparison
+ of JSON value @a v with a null pointer should be equivalent to call
+ `not v.is_null()`.
+
+ @param[in] v JSON value to consider
+ @return whether @a v is not null
+
+ @complexity Constant.
+
+ @liveexample{The example compares several JSON types to the null pointer.
+ ,operator__notequal__nullptr_t}
+
+ @since version 1.0.0
+ */
+ friend bool operator!=(const_reference v, std::nullptr_t) noexcept
+ {
+ return not v.is_null();
+ }
+
+ /*!
+ @brief comparison: not equal
+ @copydoc operator!=(const_reference, std::nullptr_t)
+ */
+ friend bool operator!=(std::nullptr_t, const_reference v) noexcept
+ {
+ return not v.is_null();
+ }
+
+ /*!
+ @brief comparison: less than
+
+ Compares whether one JSON value @a lhs is less than another JSON value @a
+ rhs according to the following rules:
+ - If @a lhs and @a rhs have the same type, the values are compared using
+ the default `<` operator.
+ - Integer and floating-point numbers are automatically converted before
+ comparison
+ - In case @a lhs and @a rhs have different types, the values are ignored
+ and the order of the types is considered, see
+ @ref operator<(const value_t, const value_t).
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether @a lhs is less than @a rhs
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__less}
+
+ @since version 1.0.0
+ */
+ friend bool operator<(const_reference lhs, const_reference rhs) noexcept
+ {
+ const auto lhs_type = lhs.type();
+ const auto rhs_type = rhs.type();
+
+ if (lhs_type == rhs_type)
+ {
+ switch (lhs_type)
+ {
+ case value_t::array:
+ {
+ return *lhs.m_value.array < *rhs.m_value.array;
+ }
+ case value_t::object:
+ {
+ return *lhs.m_value.object < *rhs.m_value.object;
+ }
+ case value_t::null:
+ {
+ return false;
+ }
+ case value_t::string:
+ {
+ return *lhs.m_value.string < *rhs.m_value.string;
+ }
+ case value_t::boolean:
+ {
+ return lhs.m_value.boolean < rhs.m_value.boolean;
+ }
+ case value_t::number_integer:
+ {
+ return lhs.m_value.number_integer < rhs.m_value.number_integer;
+ }
+ case value_t::number_unsigned:
+ {
+ return lhs.m_value.number_unsigned < rhs.m_value.number_unsigned;
+ }
+ case value_t::number_float:
+ {
+ return lhs.m_value.number_float < rhs.m_value.number_float;
+ }
+ default:
+ {
+ return false;
+ }
+ }
+ }
+ else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float)
+ {
+ return static_cast<number_float_t>(lhs.m_value.number_integer) < rhs.m_value.number_float;
+ }
+ else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer)
+ {
+ return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_integer);
+ }
+ else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float)
+ {
+ return static_cast<number_float_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_float;
+ }
+ else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned)
+ {
+ return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_unsigned);
+ }
+ else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned)
+ {
+ return lhs.m_value.number_integer < static_cast<number_integer_t>(rhs.m_value.number_unsigned);
+ }
+ else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer)
+ {
+ return static_cast<number_integer_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_integer;
+ }
+
+ // We only reach this line if we cannot compare values. In that case,
+ // we compare types. Note we have to call the operator explicitly,
+ // because MSVC has problems otherwise.
+ return operator<(lhs_type, rhs_type);
+ }
+
+ /*!
+ @brief comparison: less than or equal
+
+ Compares whether one JSON value @a lhs is less than or equal to another
+ JSON value by calculating `not (rhs < lhs)`.
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether @a lhs is less than or equal to @a rhs
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__greater}
+
+ @since version 1.0.0
+ */
+ friend bool operator<=(const_reference lhs, const_reference rhs) noexcept
+ {
+ return not (rhs < lhs);
+ }
+
+ /*!
+ @brief comparison: greater than
+
+ Compares whether one JSON value @a lhs is greater than another
+ JSON value by calculating `not (lhs <= rhs)`.
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether @a lhs is greater than to @a rhs
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__lessequal}
+
+ @since version 1.0.0
+ */
+ friend bool operator>(const_reference lhs, const_reference rhs) noexcept
+ {
+ return not (lhs <= rhs);
+ }
+
+ /*!
+ @brief comparison: greater than or equal
+
+ Compares whether one JSON value @a lhs is greater than or equal to another
+ JSON value by calculating `not (lhs < rhs)`.
+
+ @param[in] lhs first JSON value to consider
+ @param[in] rhs second JSON value to consider
+ @return whether @a lhs is greater than or equal to @a rhs
+
+ @complexity Linear.
+
+ @liveexample{The example demonstrates comparing several JSON
+ types.,operator__greaterequal}
+
+ @since version 1.0.0
+ */
+ friend bool operator>=(const_reference lhs, const_reference rhs) noexcept
+ {
+ return not (lhs < rhs);
+ }
+
+ /// @}
+
+
+ ///////////////////
+ // serialization //
+ ///////////////////
+
+ /// @name serialization
+ /// @{
+
+ /*!
+ @brief serialize to stream
+
+ Serialize the given JSON value @a j to the output stream @a o. The JSON
+ value will be serialized using the @ref dump member function. The
+ indentation of the output can be controlled with the member variable
+ `width` of the output stream @a o. For instance, using the manipulator
+ `std::setw(4)` on @a o sets the indentation level to `4` and the
+ serialization result is the same as calling `dump(4)`.
+
+ @note During serializaion, the locale and the precision of the output
+ stream @a o are changed. The original values are restored when the
+ function returns.
+
+ @param[in,out] o stream to serialize to
+ @param[in] j JSON value to serialize
+
+ @return the stream @a o
+
+ @complexity Linear.
+
+ @liveexample{The example below shows the serialization with different
+ parameters to `width` to adjust the indentation level.,operator_serialize}
+
+ @since version 1.0.0
+ */
+ friend std::ostream& operator<<(std::ostream& o, const basic_json& j)
+ {
+ // read width member and use it as indentation parameter if nonzero
+ const bool pretty_print = (o.width() > 0);
+ const auto indentation = (pretty_print ? o.width() : 0);
+
+ // reset width to 0 for subsequent calls to this stream
+ o.width(0);
+
+ // fix locale problems
+ const auto old_locale = o.imbue(std::locale(std::locale(), new DecimalSeparator));
+ // set precision
+
+ // 6, 15 or 16 digits of precision allows round-trip IEEE 754
+ // string->float->string, string->double->string or string->long
+ // double->string; to be safe, we read this value from
+ // std::numeric_limits<number_float_t>::digits10
+ const auto old_precision = o.precision(std::numeric_limits<double>::digits10);
+
+ // do the actual serialization
+ j.dump(o, pretty_print, static_cast<unsigned int>(indentation));
+
+ // reset locale and precision
+ o.imbue(old_locale);
+ o.precision(old_precision);
+ return o;
+ }
+
+ /*!
+ @brief serialize to stream
+ @copydoc operator<<(std::ostream&, const basic_json&)
+ */
+ friend std::ostream& operator>>(const basic_json& j, std::ostream& o)
+ {
+ return o << j;
+ }
+
+ /// @}
+
+
+ /////////////////////
+ // deserialization //
+ /////////////////////
+
+ /// @name deserialization
+ /// @{
+
+ /*!
+ @brief deserialize from an array
+
+ This function reads from an array of 1-byte values.
+
+ @pre Each element of the container has a size of 1 byte. Violating this
+ precondition yields undefined behavior. **This precondition is enforced
+ with a static assertion.**
+
+ @param[in] array array to read from
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @return result of the deserialization
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @liveexample{The example below demonstrates the `parse()` function reading
+ from an array.,parse__array__parser_callback_t}
+
+ @since version 2.0.3
+ */
+ template<class T, std::size_t N>
+ static basic_json parse(T (&array)[N],
+ const parser_callback_t cb = nullptr)
+ {
+ // delegate the call to the iterator-range parse overload
+ return parse(std::begin(array), std::end(array), cb);
+ }
+
+ /*!
+ @brief deserialize from string literal
+
+ @tparam CharT character/literal type with size of 1 byte
+ @param[in] s string literal to read a serialized JSON value from
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @return result of the deserialization
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+ @note String containers like `std::string` or @ref string_t can be parsed
+ with @ref parse(const ContiguousContainer&, const parser_callback_t)
+
+ @liveexample{The example below demonstrates the `parse()` function with
+ and without callback function.,parse__string__parser_callback_t}
+
+ @sa @ref parse(std::istream&, const parser_callback_t) for a version that
+ reads from an input stream
+
+ @since version 1.0.0 (originally for @ref string_t)
+ */
+ template<typename CharPT, typename std::enable_if<
+ std::is_pointer<CharPT>::value and
+ std::is_integral<typename std::remove_pointer<CharPT>::type>::value and
+ sizeof(typename std::remove_pointer<CharPT>::type) == 1, int>::type = 0>
+ static basic_json parse(const CharPT s,
+ const parser_callback_t cb = nullptr)
+ {
+ return parser(reinterpret_cast<const char*>(s), cb).parse();
+ }
+
+ /*!
+ @brief deserialize from stream
+
+ @param[in,out] i stream to read a serialized JSON value from
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @return result of the deserialization
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @liveexample{The example below demonstrates the `parse()` function with
+ and without callback function.,parse__istream__parser_callback_t}
+
+ @sa @ref parse(const char*, const parser_callback_t) for a version
+ that reads from a string
+
+ @since version 1.0.0
+ */
+ static basic_json parse(std::istream& i,
+ const parser_callback_t cb = nullptr)
+ {
+ return parser(i, cb).parse();
+ }
+
+ /*!
+ @copydoc parse(std::istream&, const parser_callback_t)
+ */
+ static basic_json parse(std::istream&& i,
+ const parser_callback_t cb = nullptr)
+ {
+ return parser(i, cb).parse();
+ }
+
+ /*!
+ @brief deserialize from an iterator range with contiguous storage
+
+ This function reads from an iterator range of a container with contiguous
+ storage of 1-byte values. Compatible container types include
+ `std::vector`, `std::string`, `std::array`, `std::valarray`, and
+ `std::initializer_list`. Furthermore, C-style arrays can be used with
+ `std::begin()`/`std::end()`. User-defined containers can be used as long
+ as they implement random-access iterators and a contiguous storage.
+
+ @pre The iterator range is contiguous. Violating this precondition yields
+ undefined behavior. **This precondition is enforced with an assertion.**
+ @pre Each element in the range has a size of 1 byte. Violating this
+ precondition yields undefined behavior. **This precondition is enforced
+ with a static assertion.**
+
+ @warning There is no way to enforce all preconditions at compile-time. If
+ the function is called with noncompliant iterators and with
+ assertions switched off, the behavior is undefined and will most
+ likely yield segmentation violation.
+
+ @tparam IteratorType iterator of container with contiguous storage
+ @param[in] first begin of the range to parse (included)
+ @param[in] last end of the range to parse (excluded)
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @return result of the deserialization
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @liveexample{The example below demonstrates the `parse()` function reading
+ from an iterator range.,parse__iteratortype__parser_callback_t}
+
+ @since version 2.0.3
+ */
+ template<class IteratorType, typename std::enable_if<
+ std::is_base_of<
+ std::random_access_iterator_tag,
+ typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0>
+ static basic_json parse(IteratorType first, IteratorType last,
+ const parser_callback_t cb = nullptr)
+ {
+ // assertion to check that the iterator range is indeed contiguous,
+ // see http://stackoverflow.com/a/35008842/266378 for more discussion
+ assert(std::accumulate(first, last, std::make_pair<bool, int>(true, 0),
+ [&first](std::pair<bool, int> res, decltype(*first) val)
+ {
+ res.first &= (val == *(std::next(std::addressof(*first), res.second++)));
+ return res;
+ }).first);
+
+ // assertion to check that each element is 1 byte long
+ static_assert(sizeof(typename std::iterator_traits<IteratorType>::value_type) == 1,
+ "each element in the iterator range must have the size of 1 byte");
+
+ // if iterator range is empty, create a parser with an empty string
+ // to generate "unexpected EOF" error message
+ if (std::distance(first, last) <= 0)
+ {
+ return parser("").parse();
+ }
+
+ return parser(first, last, cb).parse();
+ }
+
+ /*!
+ @brief deserialize from a container with contiguous storage
+
+ This function reads from a container with contiguous storage of 1-byte
+ values. Compatible container types include `std::vector`, `std::string`,
+ `std::array`, and `std::initializer_list`. User-defined containers can be
+ used as long as they implement random-access iterators and a contiguous
+ storage.
+
+ @pre The container storage is contiguous. Violating this precondition
+ yields undefined behavior. **This precondition is enforced with an
+ assertion.**
+ @pre Each element of the container has a size of 1 byte. Violating this
+ precondition yields undefined behavior. **This precondition is enforced
+ with a static assertion.**
+
+ @warning There is no way to enforce all preconditions at compile-time. If
+ the function is called with a noncompliant container and with
+ assertions switched off, the behavior is undefined and will most
+ likely yield segmentation violation.
+
+ @tparam ContiguousContainer container type with contiguous storage
+ @param[in] c container to read from
+ @param[in] cb a parser callback function of type @ref parser_callback_t
+ which is used to control the deserialization by filtering unwanted values
+ (optional)
+
+ @return result of the deserialization
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser. The complexity can be higher if the parser callback function
+ @a cb has a super-linear complexity.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @liveexample{The example below demonstrates the `parse()` function reading
+ from a contiguous container.,parse__contiguouscontainer__parser_callback_t}
+
+ @since version 2.0.3
+ */
+ template<class ContiguousContainer, typename std::enable_if<
+ not std::is_pointer<ContiguousContainer>::value and
+ std::is_base_of<
+ std::random_access_iterator_tag,
+ typename std::iterator_traits<decltype(std::begin(std::declval<ContiguousContainer const>()))>::iterator_category>::value
+ , int>::type = 0>
+ static basic_json parse(const ContiguousContainer& c,
+ const parser_callback_t cb = nullptr)
+ {
+ // delegate the call to the iterator-range parse overload
+ return parse(std::begin(c), std::end(c), cb);
+ }
+
+ /*!
+ @brief deserialize from stream
+
+ Deserializes an input stream to a JSON value.
+
+ @param[in,out] i input stream to read a serialized JSON value from
+ @param[in,out] j JSON value to write the deserialized input to
+
+ @throw std::invalid_argument in case of parse errors
+
+ @complexity Linear in the length of the input. The parser is a predictive
+ LL(1) parser.
+
+ @note A UTF-8 byte order mark is silently ignored.
+
+ @liveexample{The example below shows how a JSON value is constructed by
+ reading a serialization from a stream.,operator_deserialize}
+
+ @sa parse(std::istream&, const parser_callback_t) for a variant with a
+ parser callback function to filter values while parsing
+
+ @since version 1.0.0
+ */
+ friend std::istream& operator<<(basic_json& j, std::istream& i)
+ {
+ j = parser(i).parse();
+ return i;
+ }
+
+ /*!
+ @brief deserialize from stream
+ @copydoc operator<<(basic_json&, std::istream&)
+ */
+ friend std::istream& operator>>(std::istream& i, basic_json& j)
+ {
+ j = parser(i).parse();
+ return i;
+ }
+
+ /// @}
+
+
+ private:
+ ///////////////////////////
+ // convenience functions //
+ ///////////////////////////
+
+ /*!
+ @brief return the type as string
+
+ Returns the type name as string to be used in error messages - usually to
+ indicate that a function was called on a wrong JSON type.
+
+ @return basically a string representation of a the @a m_type member
+
+ @complexity Constant.
+
+ @since version 1.0.0
+ */
+ std::string type_name() const
+ {
+ switch (m_type)
+ {
+ case value_t::null:
+ return "null";
+ case value_t::object:
+ return "object";
+ case value_t::array:
+ return "array";
+ case value_t::string:
+ return "string";
+ case value_t::boolean:
+ return "boolean";
+ case value_t::discarded:
+ return "discarded";
+ default:
+ return "number";
+ }
+ }
+
+ /*!
+ @brief calculates the extra space to escape a JSON string
+
+ @param[in] s the string to escape
+ @return the number of characters required to escape string @a s
+
+ @complexity Linear in the length of string @a s.
+ */
+ static std::size_t extra_space(const string_t& s) noexcept
+ {
+ return std::accumulate(s.begin(), s.end(), size_t{},
+ [](size_t res, typename string_t::value_type c)
+ {
+ switch (c)
+ {
+ case '"':
+ case '\\':
+ case '\b':
+ case '\f':
+ case '\n':
+ case '\r':
+ case '\t':
+ {
+ // from c (1 byte) to \x (2 bytes)
+ return res + 1;
+ }
+
+ default:
+ {
+ if (c >= 0x00 and c <= 0x1f)
+ {
+ // from c (1 byte) to \uxxxx (6 bytes)
+ return res + 5;
+ }
+ else
+ {
+ return res;
+ }
+ }
+ }
+ });
+ }
+
+ /*!
+ @brief escape a string
+
+ Escape a string by replacing certain special characters by a sequence of
+ an escape character (backslash) and another character and other control
+ characters by a sequence of "\u" followed by a four-digit hex
+ representation.
+
+ @param[in] s the string to escape
+ @return the escaped string
+
+ @complexity Linear in the length of string @a s.
+ */
+ static string_t escape_string(const string_t& s)
+ {
+ const auto space = extra_space(s);
+ if (space == 0)
+ {
+ return s;
+ }
+
+ // create a result string of necessary size
+ string_t result(s.size() + space, '\\');
+ std::size_t pos = 0;
+
+ for (const auto& c : s)
+ {
+ switch (c)
+ {
+ // quotation mark (0x22)
+ case '"':
+ {
+ result[pos + 1] = '"';
+ pos += 2;
+ break;
+ }
+
+ // reverse solidus (0x5c)
+ case '\\':
+ {
+ // nothing to change
+ pos += 2;
+ break;
+ }
+
+ // backspace (0x08)
+ case '\b':
+ {
+ result[pos + 1] = 'b';
+ pos += 2;
+ break;
+ }
+
+ // formfeed (0x0c)
+ case '\f':
+ {
+ result[pos + 1] = 'f';
+ pos += 2;
+ break;
+ }
+
+ // newline (0x0a)
+ case '\n':
+ {
+ result[pos + 1] = 'n';
+ pos += 2;
+ break;
+ }
+
+ // carriage return (0x0d)
+ case '\r':
+ {
+ result[pos + 1] = 'r';
+ pos += 2;
+ break;
+ }
+
+ // horizontal tab (0x09)
+ case '\t':
+ {
+ result[pos + 1] = 't';
+ pos += 2;
+ break;
+ }
+
+ default:
+ {
+ if (c >= 0x00 and c <= 0x1f)
+ {
+ // convert a number 0..15 to its hex representation
+ // (0..f)
+ static const char hexify[16] =
+ {
+ '0', '1', '2', '3', '4', '5', '6', '7',
+ '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
+ };
+
+ // print character c as \uxxxx
+ for (const char m :
+ { 'u', '0', '0', hexify[c >> 4], hexify[c & 0x0f]
+ })
+ {
+ result[++pos] = m;
+ }
+
+ ++pos;
+ }
+ else
+ {
+ // all other characters are added as-is
+ result[pos++] = c;
+ }
+ break;
+ }
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief internal implementation of the serialization function
+
+ This function is called by the public member function dump and organizes
+ the serialization internally. The indentation level is propagated as
+ additional parameter. In case of arrays and objects, the function is
+ called recursively. Note that
+
+ - strings and object keys are escaped using `escape_string()`
+ - integer numbers are converted implicitly via `operator<<`
+ - floating-point numbers are converted to a string using `"%g"` format
+
+ @param[out] o stream to write to
+ @param[in] pretty_print whether the output shall be pretty-printed
+ @param[in] indent_step the indent level
+ @param[in] current_indent the current indent level (only used internally)
+ */
+ void dump(std::ostream& o,
+ const bool pretty_print,
+ const unsigned int indent_step,
+ const unsigned int current_indent = 0) const
+ {
+ // variable to hold indentation for recursive calls
+ unsigned int new_indent = current_indent;
+
+ switch (m_type)
+ {
+ case value_t::object:
+ {
+ if (m_value.object->empty())
+ {
+ o << "{}";
+ return;
+ }
+
+ o << "{";
+
+ // increase indentation
+ if (pretty_print)
+ {
+ new_indent += indent_step;
+ o << "\n";
+ }
+
+ for (auto i = m_value.object->cbegin(); i != m_value.object->cend(); ++i)
+ {
+ if (i != m_value.object->cbegin())
+ {
+ o << (pretty_print ? ",\n" : ",");
+ }
+ o << string_t(new_indent, ' ') << "\""
+ << escape_string(i->first) << "\":"
+ << (pretty_print ? " " : "");
+ i->second.dump(o, pretty_print, indent_step, new_indent);
+ }
+
+ // decrease indentation
+ if (pretty_print)
+ {
+ new_indent -= indent_step;
+ o << "\n";
+ }
+
+ o << string_t(new_indent, ' ') + "}";
+ return;
+ }
+
+ case value_t::array:
+ {
+ if (m_value.array->empty())
+ {
+ o << "[]";
+ return;
+ }
+
+ o << "[";
+
+ // increase indentation
+ if (pretty_print)
+ {
+ new_indent += indent_step;
+ o << "\n";
+ }
+
+ for (auto i = m_value.array->cbegin(); i != m_value.array->cend(); ++i)
+ {
+ if (i != m_value.array->cbegin())
+ {
+ o << (pretty_print ? ",\n" : ",");
+ }
+ o << string_t(new_indent, ' ');
+ i->dump(o, pretty_print, indent_step, new_indent);
+ }
+
+ // decrease indentation
+ if (pretty_print)
+ {
+ new_indent -= indent_step;
+ o << "\n";
+ }
+
+ o << string_t(new_indent, ' ') << "]";
+ return;
+ }
+
+ case value_t::string:
+ {
+ o << string_t("\"") << escape_string(*m_value.string) << "\"";
+ return;
+ }
+
+ case value_t::boolean:
+ {
+ o << (m_value.boolean ? "true" : "false");
+ return;
+ }
+
+ case value_t::number_integer:
+ {
+ o << m_value.number_integer;
+ return;
+ }
+
+ case value_t::number_unsigned:
+ {
+ o << m_value.number_unsigned;
+ return;
+ }
+
+ case value_t::number_float:
+ {
+ if (m_value.number_float == 0)
+ {
+ // special case for zero to get "0.0"/"-0.0"
+ o << (std::signbit(m_value.number_float) ? "-0.0" : "0.0");
+ }
+ else
+ {
+ o << m_value.number_float;
+ }
+ return;
+ }
+
+ case value_t::discarded:
+ {
+ o << "<discarded>";
+ return;
+ }
+
+ case value_t::null:
+ {
+ o << "null";
+ return;
+ }
+ }
+ }
+
+ private:
+ //////////////////////
+ // member variables //
+ //////////////////////
+
+ /// the type of the current element
+ value_t m_type = value_t::null;
+
+ /// the value of the current element
+ json_value m_value = {};
+
+
+ private:
+ ///////////////
+ // iterators //
+ ///////////////
+
+ /*!
+ @brief an iterator for primitive JSON types
+
+ This class models an iterator for primitive JSON types (boolean, number,
+ string). It's only purpose is to allow the iterator/const_iterator classes
+ to "iterate" over primitive values. Internally, the iterator is modeled by
+ a `difference_type` variable. Value begin_value (`0`) models the begin,
+ end_value (`1`) models past the end.
+ */
+ class primitive_iterator_t
+ {
+ public:
+ /// set iterator to a defined beginning
+ void set_begin() noexcept
+ {
+ m_it = begin_value;
+ }
+
+ /// set iterator to a defined past the end
+ void set_end() noexcept
+ {
+ m_it = end_value;
+ }
+
+ /// return whether the iterator can be dereferenced
+ constexpr bool is_begin() const noexcept
+ {
+ return (m_it == begin_value);
+ }
+
+ /// return whether the iterator is at end
+ constexpr bool is_end() const noexcept
+ {
+ return (m_it == end_value);
+ }
+
+ /// return reference to the value to change and compare
+ operator difference_type& () noexcept
+ {
+ return m_it;
+ }
+
+ /// return value to compare
+ constexpr operator difference_type () const noexcept
+ {
+ return m_it;
+ }
+
+ private:
+ static constexpr difference_type begin_value = 0;
+ static constexpr difference_type end_value = begin_value + 1;
+
+ /// iterator as signed integer type
+ difference_type m_it = std::numeric_limits<std::ptrdiff_t>::denorm_min();
+ };
+
+ /*!
+ @brief an iterator value
+
+ @note This structure could easily be a union, but MSVC currently does not
+ allow unions members with complex constructors, see
+ https://github.com/nlohmann/json/pull/105.
+ */
+ struct internal_iterator
+ {
+ /// iterator for JSON objects
+ typename object_t::iterator object_iterator;
+ /// iterator for JSON arrays
+ typename array_t::iterator array_iterator;
+ /// generic iterator for all other types
+ primitive_iterator_t primitive_iterator;
+
+ /// create an uninitialized internal_iterator
+ internal_iterator() noexcept
+ : object_iterator(), array_iterator(), primitive_iterator()
+ {}
+ };
+
+ /// proxy class for the iterator_wrapper functions
+ template<typename IteratorType>
+ class iteration_proxy
+ {
+ private:
+ /// helper class for iteration
+ class iteration_proxy_internal
+ {
+ private:
+ /// the iterator
+ IteratorType anchor;
+ /// an index for arrays (used to create key names)
+ size_t array_index = 0;
+
+ public:
+ explicit iteration_proxy_internal(IteratorType it) noexcept
+ : anchor(it)
+ {}
+
+ /// dereference operator (needed for range-based for)
+ iteration_proxy_internal& operator*()
+ {
+ return *this;
+ }
+
+ /// increment operator (needed for range-based for)
+ iteration_proxy_internal& operator++()
+ {
+ ++anchor;
+ ++array_index;
+
+ return *this;
+ }
+
+ /// inequality operator (needed for range-based for)
+ bool operator!= (const iteration_proxy_internal& o) const
+ {
+ return anchor != o.anchor;
+ }
+
+ /// return key of the iterator
+ typename basic_json::string_t key() const
+ {
+ assert(anchor.m_object != nullptr);
+
+ switch (anchor.m_object->type())
+ {
+ // use integer array index as key
+ case value_t::array:
+ {
+ return std::to_string(array_index);
+ }
+
+ // use key from the object
+ case value_t::object:
+ {
+ return anchor.key();
+ }
+
+ // use an empty key for all primitive types
+ default:
+ {
+ return "";
+ }
+ }
+ }
+
+ /// return value of the iterator
+ typename IteratorType::reference value() const
+ {
+ return anchor.value();
+ }
+ };
+
+ /// the container to iterate
+ typename IteratorType::reference container;
+
+ public:
+ /// construct iteration proxy from a container
+ explicit iteration_proxy(typename IteratorType::reference cont)
+ : container(cont)
+ {}
+
+ /// return iterator begin (needed for range-based for)
+ iteration_proxy_internal begin() noexcept
+ {
+ return iteration_proxy_internal(container.begin());
+ }
+
+ /// return iterator end (needed for range-based for)
+ iteration_proxy_internal end() noexcept
+ {
+ return iteration_proxy_internal(container.end());
+ }
+ };
+
+ public:
+ /*!
+ @brief a const random access iterator for the @ref basic_json class
+
+ This class implements a const iterator for the @ref basic_json class. From
+ this class, the @ref iterator class is derived.
+
+ @note An iterator is called *initialized* when a pointer to a JSON value
+ has been set (e.g., by a constructor or a copy assignment). If the
+ iterator is default-constructed, it is *uninitialized* and most
+ methods are undefined. **The library uses assertions to detect calls
+ on uninitialized iterators.**
+
+ @requirement The class satisfies the following concept requirements:
+ - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator):
+ The iterator that can be moved to point (forward and backward) to any
+ element in constant time.
+
+ @since version 1.0.0
+ */
+ class const_iterator : public std::iterator<std::random_access_iterator_tag, const basic_json>
+ {
+ /// allow basic_json to access private members
+ friend class basic_json;
+
+ public:
+ /// the type of the values when the iterator is dereferenced
+ using value_type = typename basic_json::value_type;
+ /// a type to represent differences between iterators
+ using difference_type = typename basic_json::difference_type;
+ /// defines a pointer to the type iterated over (value_type)
+ using pointer = typename basic_json::const_pointer;
+ /// defines a reference to the type iterated over (value_type)
+ using reference = typename basic_json::const_reference;
+ /// the category of the iterator
+ using iterator_category = std::bidirectional_iterator_tag;
+
+ /// default constructor
+ const_iterator() = default;
+
+ /*!
+ @brief constructor for a given JSON instance
+ @param[in] object pointer to a JSON object for this iterator
+ @pre object != nullptr
+ @post The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ explicit const_iterator(pointer object) noexcept
+ : m_object(object)
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ m_it.object_iterator = typename object_t::iterator();
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ m_it.array_iterator = typename array_t::iterator();
+ break;
+ }
+
+ default:
+ {
+ m_it.primitive_iterator = primitive_iterator_t();
+ break;
+ }
+ }
+ }
+
+ /*!
+ @brief copy constructor given a non-const iterator
+ @param[in] other iterator to copy from
+ @note It is not checked whether @a other is initialized.
+ */
+ explicit const_iterator(const iterator& other) noexcept
+ : m_object(other.m_object)
+ {
+ if (m_object != nullptr)
+ {
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ m_it.object_iterator = other.m_it.object_iterator;
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ m_it.array_iterator = other.m_it.array_iterator;
+ break;
+ }
+
+ default:
+ {
+ m_it.primitive_iterator = other.m_it.primitive_iterator;
+ break;
+ }
+ }
+ }
+ }
+
+ /*!
+ @brief copy constructor
+ @param[in] other iterator to copy from
+ @note It is not checked whether @a other is initialized.
+ */
+ const_iterator(const const_iterator& other) noexcept
+ : m_object(other.m_object), m_it(other.m_it)
+ {}
+
+ /*!
+ @brief copy assignment
+ @param[in,out] other iterator to copy from
+ @note It is not checked whether @a other is initialized.
+ */
+ const_iterator& operator=(const_iterator other) noexcept(
+ std::is_nothrow_move_constructible<pointer>::value and
+ std::is_nothrow_move_assignable<pointer>::value and
+ std::is_nothrow_move_constructible<internal_iterator>::value and
+ std::is_nothrow_move_assignable<internal_iterator>::value
+ )
+ {
+ std::swap(m_object, other.m_object);
+ std::swap(m_it, other.m_it);
+ return *this;
+ }
+
+ private:
+ /*!
+ @brief set the iterator to the first value
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ void set_begin() noexcept
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ m_it.object_iterator = m_object->m_value.object->begin();
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ m_it.array_iterator = m_object->m_value.array->begin();
+ break;
+ }
+
+ case basic_json::value_t::null:
+ {
+ // set to end so begin()==end() is true: null is empty
+ m_it.primitive_iterator.set_end();
+ break;
+ }
+
+ default:
+ {
+ m_it.primitive_iterator.set_begin();
+ break;
+ }
+ }
+ }
+
+ /*!
+ @brief set the iterator past the last value
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ void set_end() noexcept
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ m_it.object_iterator = m_object->m_value.object->end();
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ m_it.array_iterator = m_object->m_value.array->end();
+ break;
+ }
+
+ default:
+ {
+ m_it.primitive_iterator.set_end();
+ break;
+ }
+ }
+ }
+
+ public:
+ /*!
+ @brief return a reference to the value pointed to by the iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ reference operator*() const
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ assert(m_it.object_iterator != m_object->m_value.object->end());
+ return m_it.object_iterator->second;
+ }
+
+ case basic_json::value_t::array:
+ {
+ assert(m_it.array_iterator != m_object->m_value.array->end());
+ return *m_it.array_iterator;
+ }
+
+ case basic_json::value_t::null:
+ {
+ throw std::out_of_range("cannot get value");
+ }
+
+ default:
+ {
+ if (m_it.primitive_iterator.is_begin())
+ {
+ return *m_object;
+ }
+ else
+ {
+ throw std::out_of_range("cannot get value");
+ }
+ }
+ }
+ }
+
+ /*!
+ @brief dereference the iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ pointer operator->() const
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ assert(m_it.object_iterator != m_object->m_value.object->end());
+ return &(m_it.object_iterator->second);
+ }
+
+ case basic_json::value_t::array:
+ {
+ assert(m_it.array_iterator != m_object->m_value.array->end());
+ return &*m_it.array_iterator;
+ }
+
+ default:
+ {
+ if (m_it.primitive_iterator.is_begin())
+ {
+ return m_object;
+ }
+ else
+ {
+ throw std::out_of_range("cannot get value");
+ }
+ }
+ }
+ }
+
+ /*!
+ @brief post-increment (it++)
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator operator++(int)
+ {
+ auto result = *this;
+ ++(*this);
+ return result;
+ }
+
+ /*!
+ @brief pre-increment (++it)
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator& operator++()
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ std::advance(m_it.object_iterator, 1);
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ std::advance(m_it.array_iterator, 1);
+ break;
+ }
+
+ default:
+ {
+ ++m_it.primitive_iterator;
+ break;
+ }
+ }
+
+ return *this;
+ }
+
+ /*!
+ @brief post-decrement (it--)
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator operator--(int)
+ {
+ auto result = *this;
+ --(*this);
+ return result;
+ }
+
+ /*!
+ @brief pre-decrement (--it)
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator& operator--()
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ std::advance(m_it.object_iterator, -1);
+ break;
+ }
+
+ case basic_json::value_t::array:
+ {
+ std::advance(m_it.array_iterator, -1);
+ break;
+ }
+
+ default:
+ {
+ --m_it.primitive_iterator;
+ break;
+ }
+ }
+
+ return *this;
+ }
+
+ /*!
+ @brief comparison: equal
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator==(const const_iterator& other) const
+ {
+ // if objects are not the same, the comparison is undefined
+ if (m_object != other.m_object)
+ {
+ throw std::domain_error("cannot compare iterators of different containers");
+ }
+
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ return (m_it.object_iterator == other.m_it.object_iterator);
+ }
+
+ case basic_json::value_t::array:
+ {
+ return (m_it.array_iterator == other.m_it.array_iterator);
+ }
+
+ default:
+ {
+ return (m_it.primitive_iterator == other.m_it.primitive_iterator);
+ }
+ }
+ }
+
+ /*!
+ @brief comparison: not equal
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator!=(const const_iterator& other) const
+ {
+ return not operator==(other);
+ }
+
+ /*!
+ @brief comparison: smaller
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator<(const const_iterator& other) const
+ {
+ // if objects are not the same, the comparison is undefined
+ if (m_object != other.m_object)
+ {
+ throw std::domain_error("cannot compare iterators of different containers");
+ }
+
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ throw std::domain_error("cannot compare order of object iterators");
+ }
+
+ case basic_json::value_t::array:
+ {
+ return (m_it.array_iterator < other.m_it.array_iterator);
+ }
+
+ default:
+ {
+ return (m_it.primitive_iterator < other.m_it.primitive_iterator);
+ }
+ }
+ }
+
+ /*!
+ @brief comparison: less than or equal
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator<=(const const_iterator& other) const
+ {
+ return not other.operator < (*this);
+ }
+
+ /*!
+ @brief comparison: greater than
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator>(const const_iterator& other) const
+ {
+ return not operator<=(other);
+ }
+
+ /*!
+ @brief comparison: greater than or equal
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ bool operator>=(const const_iterator& other) const
+ {
+ return not operator<(other);
+ }
+
+ /*!
+ @brief add to iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator& operator+=(difference_type i)
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ throw std::domain_error("cannot use offsets with object iterators");
+ }
+
+ case basic_json::value_t::array:
+ {
+ std::advance(m_it.array_iterator, i);
+ break;
+ }
+
+ default:
+ {
+ m_it.primitive_iterator += i;
+ break;
+ }
+ }
+
+ return *this;
+ }
+
+ /*!
+ @brief subtract from iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator& operator-=(difference_type i)
+ {
+ return operator+=(-i);
+ }
+
+ /*!
+ @brief add to iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator operator+(difference_type i)
+ {
+ auto result = *this;
+ result += i;
+ return result;
+ }
+
+ /*!
+ @brief subtract from iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ const_iterator operator-(difference_type i)
+ {
+ auto result = *this;
+ result -= i;
+ return result;
+ }
+
+ /*!
+ @brief return difference
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ difference_type operator-(const const_iterator& other) const
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ throw std::domain_error("cannot use offsets with object iterators");
+ }
+
+ case basic_json::value_t::array:
+ {
+ return m_it.array_iterator - other.m_it.array_iterator;
+ }
+
+ default:
+ {
+ return m_it.primitive_iterator - other.m_it.primitive_iterator;
+ }
+ }
+ }
+
+ /*!
+ @brief access to successor
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ reference operator[](difference_type n) const
+ {
+ assert(m_object != nullptr);
+
+ switch (m_object->m_type)
+ {
+ case basic_json::value_t::object:
+ {
+ throw std::domain_error("cannot use operator[] for object iterators");
+ }
+
+ case basic_json::value_t::array:
+ {
+ return *std::next(m_it.array_iterator, n);
+ }
+
+ case basic_json::value_t::null:
+ {
+ throw std::out_of_range("cannot get value");
+ }
+
+ default:
+ {
+ if (m_it.primitive_iterator == -n)
+ {
+ return *m_object;
+ }
+ else
+ {
+ throw std::out_of_range("cannot get value");
+ }
+ }
+ }
+ }
+
+ /*!
+ @brief return the key of an object iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ typename object_t::key_type key() const
+ {
+ assert(m_object != nullptr);
+
+ if (m_object->is_object())
+ {
+ return m_it.object_iterator->first;
+ }
+ else
+ {
+ throw std::domain_error("cannot use key() for non-object iterators");
+ }
+ }
+
+ /*!
+ @brief return the value of an iterator
+ @pre The iterator is initialized; i.e. `m_object != nullptr`.
+ */
+ reference value() const
+ {
+ return operator*();
+ }
+
+ private:
+ /// associated JSON instance
+ pointer m_object = nullptr;
+ /// the actual iterator of the associated instance
+ internal_iterator m_it = internal_iterator();
+ };
+
+ /*!
+ @brief a mutable random access iterator for the @ref basic_json class
+
+ @requirement The class satisfies the following concept requirements:
+ - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator):
+ The iterator that can be moved to point (forward and backward) to any
+ element in constant time.
+ - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator):
+ It is possible to write to the pointed-to element.
+
+ @since version 1.0.0
+ */
+ class iterator : public const_iterator
+ {
+ public:
+ using base_iterator = const_iterator;
+ using pointer = typename basic_json::pointer;
+ using reference = typename basic_json::reference;
+
+ /// default constructor
+ iterator() = default;
+
+ /// constructor for a given JSON instance
+ explicit iterator(pointer object) noexcept
+ : base_iterator(object)
+ {}
+
+ /// copy constructor
+ iterator(const iterator& other) noexcept
+ : base_iterator(other)
+ {}
+
+ /// copy assignment
+ iterator& operator=(iterator other) noexcept(
+ std::is_nothrow_move_constructible<pointer>::value and
+ std::is_nothrow_move_assignable<pointer>::value and
+ std::is_nothrow_move_constructible<internal_iterator>::value and
+ std::is_nothrow_move_assignable<internal_iterator>::value
+ )
+ {
+ base_iterator::operator=(other);
+ return *this;
+ }
+
+ /// return a reference to the value pointed to by the iterator
+ reference operator*() const
+ {
+ return const_cast<reference>(base_iterator::operator*());
+ }
+
+ /// dereference the iterator
+ pointer operator->() const
+ {
+ return const_cast<pointer>(base_iterator::operator->());
+ }
+
+ /// post-increment (it++)
+ iterator operator++(int)
+ {
+ iterator result = *this;
+ base_iterator::operator++();
+ return result;
+ }
+
+ /// pre-increment (++it)
+ iterator& operator++()
+ {
+ base_iterator::operator++();
+ return *this;
+ }
+
+ /// post-decrement (it--)
+ iterator operator--(int)
+ {
+ iterator result = *this;
+ base_iterator::operator--();
+ return result;
+ }
+
+ /// pre-decrement (--it)
+ iterator& operator--()
+ {
+ base_iterator::operator--();
+ return *this;
+ }
+
+ /// add to iterator
+ iterator& operator+=(difference_type i)
+ {
+ base_iterator::operator+=(i);
+ return *this;
+ }
+
+ /// subtract from iterator
+ iterator& operator-=(difference_type i)
+ {
+ base_iterator::operator-=(i);
+ return *this;
+ }
+
+ /// add to iterator
+ iterator operator+(difference_type i)
+ {
+ auto result = *this;
+ result += i;
+ return result;
+ }
+
+ /// subtract from iterator
+ iterator operator-(difference_type i)
+ {
+ auto result = *this;
+ result -= i;
+ return result;
+ }
+
+ /// return difference
+ difference_type operator-(const iterator& other) const
+ {
+ return base_iterator::operator-(other);
+ }
+
+ /// access to successor
+ reference operator[](difference_type n) const
+ {
+ return const_cast<reference>(base_iterator::operator[](n));
+ }
+
+ /// return the value of an iterator
+ reference value() const
+ {
+ return const_cast<reference>(base_iterator::value());
+ }
+ };
+
+ /*!
+ @brief a template for a reverse iterator class
+
+ @tparam Base the base iterator type to reverse. Valid types are @ref
+ iterator (to create @ref reverse_iterator) and @ref const_iterator (to
+ create @ref const_reverse_iterator).
+
+ @requirement The class satisfies the following concept requirements:
+ - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator):
+ The iterator that can be moved to point (forward and backward) to any
+ element in constant time.
+ - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator):
+ It is possible to write to the pointed-to element (only if @a Base is
+ @ref iterator).
+
+ @since version 1.0.0
+ */
+ template<typename Base>
+ class json_reverse_iterator : public std::reverse_iterator<Base>
+ {
+ public:
+ /// shortcut to the reverse iterator adaptor
+ using base_iterator = std::reverse_iterator<Base>;
+ /// the reference type for the pointed-to element
+ using reference = typename Base::reference;
+
+ /// create reverse iterator from iterator
+ json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
+ : base_iterator(it)
+ {}
+
+ /// create reverse iterator from base class
+ json_reverse_iterator(const base_iterator& it) noexcept
+ : base_iterator(it)
+ {}
+
+ /// post-increment (it++)
+ json_reverse_iterator operator++(int)
+ {
+ return base_iterator::operator++(1);
+ }
+
+ /// pre-increment (++it)
+ json_reverse_iterator& operator++()
+ {
+ base_iterator::operator++();
+ return *this;
+ }
+
+ /// post-decrement (it--)
+ json_reverse_iterator operator--(int)
+ {
+ return base_iterator::operator--(1);
+ }
+
+ /// pre-decrement (--it)
+ json_reverse_iterator& operator--()
+ {
+ base_iterator::operator--();
+ return *this;
+ }
+
+ /// add to iterator
+ json_reverse_iterator& operator+=(difference_type i)
+ {
+ base_iterator::operator+=(i);
+ return *this;
+ }
+
+ /// add to iterator
+ json_reverse_iterator operator+(difference_type i) const
+ {
+ auto result = *this;
+ result += i;
+ return result;
+ }
+
+ /// subtract from iterator
+ json_reverse_iterator operator-(difference_type i) const
+ {
+ auto result = *this;
+ result -= i;
+ return result;
+ }
+
+ /// return difference
+ difference_type operator-(const json_reverse_iterator& other) const
+ {
+ return this->base() - other.base();
+ }
+
+ /// access to successor
+ reference operator[](difference_type n) const
+ {
+ return *(this->operator+(n));
+ }
+
+ /// return the key of an object iterator
+ typename object_t::key_type key() const
+ {
+ auto it = --this->base();
+ return it.key();
+ }
+
+ /// return the value of an iterator
+ reference value() const
+ {
+ auto it = --this->base();
+ return it.operator * ();
+ }
+ };
+
+
+ private:
+ //////////////////////
+ // lexer and parser //
+ //////////////////////
+
+ /*!
+ @brief lexical analysis
+
+ This class organizes the lexical analysis during JSON deserialization. The
+ core of it is a scanner generated by [re2c](http://re2c.org) that
+ processes a buffer and recognizes tokens according to RFC 7159.
+ */
+ class lexer
+ {
+ public:
+ /// token types for the parser
+ enum class token_type
+ {
+ uninitialized, ///< indicating the scanner is uninitialized
+ literal_true, ///< the `true` literal
+ literal_false, ///< the `false` literal
+ literal_null, ///< the `null` literal
+ value_string, ///< a string -- use get_string() for actual value
+ value_number, ///< a number -- use get_number() for actual value
+ begin_array, ///< the character for array begin `[`
+ begin_object, ///< the character for object begin `{`
+ end_array, ///< the character for array end `]`
+ end_object, ///< the character for object end `}`
+ name_separator, ///< the name separator `:`
+ value_separator, ///< the value separator `,`
+ parse_error, ///< indicating a parse error
+ end_of_input ///< indicating the end of the input buffer
+ };
+
+ /// the char type to use in the lexer
+ using lexer_char_t = unsigned char;
+
+ /// a lexer from a buffer with given length
+ lexer(const lexer_char_t* buff, const size_t len) noexcept
+ : m_content(buff)
+ {
+ assert(m_content != nullptr);
+ m_start = m_cursor = m_content;
+ m_limit = m_content + len;
+ }
+
+ /// a lexer from an input stream
+ explicit lexer(std::istream& s)
+ : m_stream(&s), m_line_buffer()
+ {
+ // fill buffer
+ fill_line_buffer();
+
+ // skip UTF-8 byte-order mark
+ if (m_line_buffer.size() >= 3 and m_line_buffer.substr(0, 3) == "\xEF\xBB\xBF")
+ {
+ m_line_buffer[0] = ' ';
+ m_line_buffer[1] = ' ';
+ m_line_buffer[2] = ' ';
+ }
+ }
+
+ // switch off unwanted functions (due to pointer members)
+ lexer() = delete;
+ lexer(const lexer&) = delete;
+ lexer operator=(const lexer&) = delete;
+
+ /*!
+ @brief create a string from one or two Unicode code points
+
+ There are two cases: (1) @a codepoint1 is in the Basic Multilingual
+ Plane (U+0000 through U+FFFF) and @a codepoint2 is 0, or (2)
+ @a codepoint1 and @a codepoint2 are a UTF-16 surrogate pair to
+ represent a code point above U+FFFF.
+
+ @param[in] codepoint1 the code point (can be high surrogate)
+ @param[in] codepoint2 the code point (can be low surrogate or 0)
+
+ @return string representation of the code point; the length of the
+ result string is between 1 and 4 characters.
+
+ @throw std::out_of_range if code point is > 0x10ffff; example: `"code
+ points above 0x10FFFF are invalid"`
+ @throw std::invalid_argument if the low surrogate is invalid; example:
+ `""missing or wrong low surrogate""`
+
+ @complexity Constant.
+
+ @see <http://en.wikipedia.org/wiki/UTF-8#Sample_code>
+ */
+ static string_t to_unicode(const std::size_t codepoint1,
+ const std::size_t codepoint2 = 0)
+ {
+ // calculate the code point from the given code points
+ std::size_t codepoint = codepoint1;
+
+ // check if codepoint1 is a high surrogate
+ if (codepoint1 >= 0xD800 and codepoint1 <= 0xDBFF)
+ {
+ // check if codepoint2 is a low surrogate
+ if (codepoint2 >= 0xDC00 and codepoint2 <= 0xDFFF)
+ {
+ codepoint =
+ // high surrogate occupies the most significant 22 bits
+ (codepoint1 << 10)
+ // low surrogate occupies the least significant 15 bits
+ + codepoint2
+ // there is still the 0xD800, 0xDC00 and 0x10000 noise
+ // in the result so we have to subtract with:
+ // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00
+ - 0x35FDC00;
+ }
+ else
+ {
+ throw std::invalid_argument("missing or wrong low surrogate");
+ }
+ }
+
+ string_t result;
+
+ if (codepoint < 0x80)
+ {
+ // 1-byte characters: 0xxxxxxx (ASCII)
+ result.append(1, static_cast<typename string_t::value_type>(codepoint));
+ }
+ else if (codepoint <= 0x7ff)
+ {
+ // 2-byte characters: 110xxxxx 10xxxxxx
+ result.append(1, static_cast<typename string_t::value_type>(0xC0 | ((codepoint >> 6) & 0x1F)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F)));
+ }
+ else if (codepoint <= 0xffff)
+ {
+ // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx
+ result.append(1, static_cast<typename string_t::value_type>(0xE0 | ((codepoint >> 12) & 0x0F)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 6) & 0x3F)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F)));
+ }
+ else if (codepoint <= 0x10ffff)
+ {
+ // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+ result.append(1, static_cast<typename string_t::value_type>(0xF0 | ((codepoint >> 18) & 0x07)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 12) & 0x3F)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 6) & 0x3F)));
+ result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F)));
+ }
+ else
+ {
+ throw std::out_of_range("code points above 0x10FFFF are invalid");
+ }
+
+ return result;
+ }
+
+ /// return name of values of type token_type (only used for errors)
+ static std::string token_type_name(const token_type t)
+ {
+ switch (t)
+ {
+ case token_type::uninitialized:
+ return "<uninitialized>";
+ case token_type::literal_true:
+ return "true literal";
+ case token_type::literal_false:
+ return "false literal";
+ case token_type::literal_null:
+ return "null literal";
+ case token_type::value_string:
+ return "string literal";
+ case token_type::value_number:
+ return "number literal";
+ case token_type::begin_array:
+ return "'['";
+ case token_type::begin_object:
+ return "'{'";
+ case token_type::end_array:
+ return "']'";
+ case token_type::end_object:
+ return "'}'";
+ case token_type::name_separator:
+ return "':'";
+ case token_type::value_separator:
+ return "','";
+ case token_type::parse_error:
+ return "<parse error>";
+ case token_type::end_of_input:
+ return "end of input";
+ default:
+ {
+ // catch non-enum values
+ return "unknown token"; // LCOV_EXCL_LINE
+ }
+ }
+ }
+
+ /*!
+ This function implements a scanner for JSON. It is specified using
+ regular expressions that try to follow RFC 7159 as close as possible.
+ These regular expressions are then translated into a minimized
+ deterministic finite automaton (DFA) by the tool
+ [re2c](http://re2c.org). As a result, the translated code for this
+ function consists of a large block of code with `goto` jumps.
+
+ @return the class of the next token read from the buffer
+
+ @complexity Linear in the length of the input.\n
+
+ Proposition: The loop below will always terminate for finite input.\n
+
+ Proof (by contradiction): Assume a finite input. To loop forever, the
+ loop must never hit code with a `break` statement. The only code
+ snippets without a `break` statement are the continue statements for
+ whitespace and byte-order-marks. To loop forever, the input must be an
+ infinite sequence of whitespace or byte-order-marks. This contradicts
+ the assumption of finite input, q.e.d.
+ */
+ token_type scan()
+ {
+ while (true)
+ {
+ // pointer for backtracking information
+ m_marker = nullptr;
+
+ // remember the begin of the token
+ m_start = m_cursor;
+ assert(m_start != nullptr);
+
+
+ {
+ lexer_char_t yych;
+ unsigned int yyaccept = 0;
+ static const unsigned char yybm[] =
+ {
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 32, 32, 0, 0, 32, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 160, 128, 0, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 192, 192, 192, 192, 192, 192, 192, 192,
+ 192, 192, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 0, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ };
+ if ((m_limit - m_cursor) < 5)
+ {
+ fill_line_buffer(5); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yybm[0 + yych] & 32)
+ {
+ goto basic_json_parser_6;
+ }
+ if (yych <= '[')
+ {
+ if (yych <= '-')
+ {
+ if (yych <= '"')
+ {
+ if (yych <= 0x00)
+ {
+ goto basic_json_parser_2;
+ }
+ if (yych <= '!')
+ {
+ goto basic_json_parser_4;
+ }
+ goto basic_json_parser_9;
+ }
+ else
+ {
+ if (yych <= '+')
+ {
+ goto basic_json_parser_4;
+ }
+ if (yych <= ',')
+ {
+ goto basic_json_parser_10;
+ }
+ goto basic_json_parser_12;
+ }
+ }
+ else
+ {
+ if (yych <= '9')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_4;
+ }
+ if (yych <= '0')
+ {
+ goto basic_json_parser_13;
+ }
+ goto basic_json_parser_15;
+ }
+ else
+ {
+ if (yych <= ':')
+ {
+ goto basic_json_parser_17;
+ }
+ if (yych <= 'Z')
+ {
+ goto basic_json_parser_4;
+ }
+ goto basic_json_parser_19;
+ }
+ }
+ }
+ else
+ {
+ if (yych <= 'n')
+ {
+ if (yych <= 'e')
+ {
+ if (yych == ']')
+ {
+ goto basic_json_parser_21;
+ }
+ goto basic_json_parser_4;
+ }
+ else
+ {
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_23;
+ }
+ if (yych <= 'm')
+ {
+ goto basic_json_parser_4;
+ }
+ goto basic_json_parser_24;
+ }
+ }
+ else
+ {
+ if (yych <= 'z')
+ {
+ if (yych == 't')
+ {
+ goto basic_json_parser_25;
+ }
+ goto basic_json_parser_4;
+ }
+ else
+ {
+ if (yych <= '{')
+ {
+ goto basic_json_parser_26;
+ }
+ if (yych == '}')
+ {
+ goto basic_json_parser_28;
+ }
+ goto basic_json_parser_4;
+ }
+ }
+ }
+basic_json_parser_2:
+ ++m_cursor;
+ {
+ last_token_type = token_type::end_of_input;
+ break;
+ }
+basic_json_parser_4:
+ ++m_cursor;
+basic_json_parser_5:
+ {
+ last_token_type = token_type::parse_error;
+ break;
+ }
+basic_json_parser_6:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yybm[0 + yych] & 32)
+ {
+ goto basic_json_parser_6;
+ }
+ {
+ continue;
+ }
+basic_json_parser_9:
+ yyaccept = 0;
+ yych = *(m_marker = ++m_cursor);
+ if (yych <= 0x1F)
+ {
+ goto basic_json_parser_5;
+ }
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_31;
+ }
+ if (yych <= 0xC1)
+ {
+ goto basic_json_parser_5;
+ }
+ if (yych <= 0xF4)
+ {
+ goto basic_json_parser_31;
+ }
+ goto basic_json_parser_5;
+basic_json_parser_10:
+ ++m_cursor;
+ {
+ last_token_type = token_type::value_separator;
+ break;
+ }
+basic_json_parser_12:
+ yych = *++m_cursor;
+ if (yych <= '/')
+ {
+ goto basic_json_parser_5;
+ }
+ if (yych <= '0')
+ {
+ goto basic_json_parser_13;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_15;
+ }
+ goto basic_json_parser_5;
+basic_json_parser_13:
+ yyaccept = 1;
+ yych = *(m_marker = ++m_cursor);
+ if (yych <= 'D')
+ {
+ if (yych == '.')
+ {
+ goto basic_json_parser_43;
+ }
+ }
+ else
+ {
+ if (yych <= 'E')
+ {
+ goto basic_json_parser_44;
+ }
+ if (yych == 'e')
+ {
+ goto basic_json_parser_44;
+ }
+ }
+basic_json_parser_14:
+ {
+ last_token_type = token_type::value_number;
+ break;
+ }
+basic_json_parser_15:
+ yyaccept = 1;
+ m_marker = ++m_cursor;
+ if ((m_limit - m_cursor) < 3)
+ {
+ fill_line_buffer(3); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yybm[0 + yych] & 64)
+ {
+ goto basic_json_parser_15;
+ }
+ if (yych <= 'D')
+ {
+ if (yych == '.')
+ {
+ goto basic_json_parser_43;
+ }
+ goto basic_json_parser_14;
+ }
+ else
+ {
+ if (yych <= 'E')
+ {
+ goto basic_json_parser_44;
+ }
+ if (yych == 'e')
+ {
+ goto basic_json_parser_44;
+ }
+ goto basic_json_parser_14;
+ }
+basic_json_parser_17:
+ ++m_cursor;
+ {
+ last_token_type = token_type::name_separator;
+ break;
+ }
+basic_json_parser_19:
+ ++m_cursor;
+ {
+ last_token_type = token_type::begin_array;
+ break;
+ }
+basic_json_parser_21:
+ ++m_cursor;
+ {
+ last_token_type = token_type::end_array;
+ break;
+ }
+basic_json_parser_23:
+ yyaccept = 0;
+ yych = *(m_marker = ++m_cursor);
+ if (yych == 'a')
+ {
+ goto basic_json_parser_45;
+ }
+ goto basic_json_parser_5;
+basic_json_parser_24:
+ yyaccept = 0;
+ yych = *(m_marker = ++m_cursor);
+ if (yych == 'u')
+ {
+ goto basic_json_parser_46;
+ }
+ goto basic_json_parser_5;
+basic_json_parser_25:
+ yyaccept = 0;
+ yych = *(m_marker = ++m_cursor);
+ if (yych == 'r')
+ {
+ goto basic_json_parser_47;
+ }
+ goto basic_json_parser_5;
+basic_json_parser_26:
+ ++m_cursor;
+ {
+ last_token_type = token_type::begin_object;
+ break;
+ }
+basic_json_parser_28:
+ ++m_cursor;
+ {
+ last_token_type = token_type::end_object;
+ break;
+ }
+basic_json_parser_30:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+basic_json_parser_31:
+ if (yybm[0 + yych] & 128)
+ {
+ goto basic_json_parser_30;
+ }
+ if (yych <= 0xE0)
+ {
+ if (yych <= '\\')
+ {
+ if (yych <= 0x1F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '"')
+ {
+ goto basic_json_parser_33;
+ }
+ goto basic_json_parser_35;
+ }
+ else
+ {
+ if (yych <= 0xC1)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xDF)
+ {
+ goto basic_json_parser_36;
+ }
+ goto basic_json_parser_37;
+ }
+ }
+ else
+ {
+ if (yych <= 0xEF)
+ {
+ if (yych == 0xED)
+ {
+ goto basic_json_parser_39;
+ }
+ goto basic_json_parser_38;
+ }
+ else
+ {
+ if (yych <= 0xF0)
+ {
+ goto basic_json_parser_40;
+ }
+ if (yych <= 0xF3)
+ {
+ goto basic_json_parser_41;
+ }
+ if (yych <= 0xF4)
+ {
+ goto basic_json_parser_42;
+ }
+ }
+ }
+basic_json_parser_32:
+ m_cursor = m_marker;
+ if (yyaccept == 0)
+ {
+ goto basic_json_parser_5;
+ }
+ else
+ {
+ goto basic_json_parser_14;
+ }
+basic_json_parser_33:
+ ++m_cursor;
+ {
+ last_token_type = token_type::value_string;
+ break;
+ }
+basic_json_parser_35:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 'e')
+ {
+ if (yych <= '/')
+ {
+ if (yych == '"')
+ {
+ goto basic_json_parser_30;
+ }
+ if (yych <= '.')
+ {
+ goto basic_json_parser_32;
+ }
+ goto basic_json_parser_30;
+ }
+ else
+ {
+ if (yych <= '\\')
+ {
+ if (yych <= '[')
+ {
+ goto basic_json_parser_32;
+ }
+ goto basic_json_parser_30;
+ }
+ else
+ {
+ if (yych == 'b')
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+ }
+ }
+ }
+ else
+ {
+ if (yych <= 'q')
+ {
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_30;
+ }
+ if (yych == 'n')
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 's')
+ {
+ if (yych <= 'r')
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 't')
+ {
+ goto basic_json_parser_30;
+ }
+ if (yych <= 'u')
+ {
+ goto basic_json_parser_48;
+ }
+ goto basic_json_parser_32;
+ }
+ }
+ }
+basic_json_parser_36:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xBF)
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_37:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x9F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xBF)
+ {
+ goto basic_json_parser_36;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_38:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xBF)
+ {
+ goto basic_json_parser_36;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_39:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0x9F)
+ {
+ goto basic_json_parser_36;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_40:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x8F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xBF)
+ {
+ goto basic_json_parser_38;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_41:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0xBF)
+ {
+ goto basic_json_parser_38;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_42:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 0x7F)
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 0x8F)
+ {
+ goto basic_json_parser_38;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_43:
+ yych = *++m_cursor;
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_49;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_44:
+ yych = *++m_cursor;
+ if (yych <= ',')
+ {
+ if (yych == '+')
+ {
+ goto basic_json_parser_51;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= '-')
+ {
+ goto basic_json_parser_51;
+ }
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_52;
+ }
+ goto basic_json_parser_32;
+ }
+basic_json_parser_45:
+ yych = *++m_cursor;
+ if (yych == 'l')
+ {
+ goto basic_json_parser_54;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_46:
+ yych = *++m_cursor;
+ if (yych == 'l')
+ {
+ goto basic_json_parser_55;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_47:
+ yych = *++m_cursor;
+ if (yych == 'u')
+ {
+ goto basic_json_parser_56;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_48:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= '@')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_57;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 'F')
+ {
+ goto basic_json_parser_57;
+ }
+ if (yych <= '`')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_57;
+ }
+ goto basic_json_parser_32;
+ }
+basic_json_parser_49:
+ yyaccept = 1;
+ m_marker = ++m_cursor;
+ if ((m_limit - m_cursor) < 3)
+ {
+ fill_line_buffer(3); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= 'D')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_14;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_49;
+ }
+ goto basic_json_parser_14;
+ }
+ else
+ {
+ if (yych <= 'E')
+ {
+ goto basic_json_parser_44;
+ }
+ if (yych == 'e')
+ {
+ goto basic_json_parser_44;
+ }
+ goto basic_json_parser_14;
+ }
+basic_json_parser_51:
+ yych = *++m_cursor;
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych >= ':')
+ {
+ goto basic_json_parser_32;
+ }
+basic_json_parser_52:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= '/')
+ {
+ goto basic_json_parser_14;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_52;
+ }
+ goto basic_json_parser_14;
+basic_json_parser_54:
+ yych = *++m_cursor;
+ if (yych == 's')
+ {
+ goto basic_json_parser_58;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_55:
+ yych = *++m_cursor;
+ if (yych == 'l')
+ {
+ goto basic_json_parser_59;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_56:
+ yych = *++m_cursor;
+ if (yych == 'e')
+ {
+ goto basic_json_parser_61;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_57:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= '@')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_63;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 'F')
+ {
+ goto basic_json_parser_63;
+ }
+ if (yych <= '`')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_63;
+ }
+ goto basic_json_parser_32;
+ }
+basic_json_parser_58:
+ yych = *++m_cursor;
+ if (yych == 'e')
+ {
+ goto basic_json_parser_64;
+ }
+ goto basic_json_parser_32;
+basic_json_parser_59:
+ ++m_cursor;
+ {
+ last_token_type = token_type::literal_null;
+ break;
+ }
+basic_json_parser_61:
+ ++m_cursor;
+ {
+ last_token_type = token_type::literal_true;
+ break;
+ }
+basic_json_parser_63:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= '@')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_66;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 'F')
+ {
+ goto basic_json_parser_66;
+ }
+ if (yych <= '`')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_66;
+ }
+ goto basic_json_parser_32;
+ }
+basic_json_parser_64:
+ ++m_cursor;
+ {
+ last_token_type = token_type::literal_false;
+ break;
+ }
+basic_json_parser_66:
+ ++m_cursor;
+ if (m_limit <= m_cursor)
+ {
+ fill_line_buffer(1); // LCOV_EXCL_LINE
+ }
+ yych = *m_cursor;
+ if (yych <= '@')
+ {
+ if (yych <= '/')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= '9')
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+ }
+ else
+ {
+ if (yych <= 'F')
+ {
+ goto basic_json_parser_30;
+ }
+ if (yych <= '`')
+ {
+ goto basic_json_parser_32;
+ }
+ if (yych <= 'f')
+ {
+ goto basic_json_parser_30;
+ }
+ goto basic_json_parser_32;
+ }
+ }
+
+ }
+
+ return last_token_type;
+ }
+
+ /*!
+ @brief append data from the stream to the line buffer
+
+ This function is called by the scan() function when the end of the
+ buffer (`m_limit`) is reached and the `m_cursor` pointer cannot be
+ incremented without leaving the limits of the line buffer. Note re2c
+ decides when to call this function.
+
+ If the lexer reads from contiguous storage, there is no trailing null
+ byte. Therefore, this function must make sure to add these padding
+ null bytes.
+
+ If the lexer reads from an input stream, this function reads the next
+ line of the input.
+
+ @pre
+ p p p p p p u u u u u x . . . . . .
+ ^ ^ ^ ^
+ m_content m_start | m_limit
+ m_cursor
+
+ @post
+ u u u u u x x x x x x x . . . . . .
+ ^ ^ ^
+ | m_cursor m_limit
+ m_start
+ m_content
+ */
+ void fill_line_buffer(size_t n = 0)
+ {
+ // number of processed characters (p)
+ const auto offset_start = m_start - m_content;
+ // offset for m_marker wrt. to m_start
+ const auto offset_marker = (m_marker == nullptr) ? 0 : m_marker - m_start;
+ // number of unprocessed characters (u)
+ const auto offset_cursor = m_cursor - m_start;
+
+ // no stream is used or end of file is reached
+ if (m_stream == nullptr or m_stream->eof())
+ {
+ // skip this part if we are already using the line buffer
+ if (m_start != reinterpret_cast<const lexer_char_t*>(m_line_buffer.data()))
+ {
+ // copy unprocessed characters to line buffer
+ m_line_buffer.clear();
+ for (m_cursor = m_start; m_cursor != m_limit; ++m_cursor)
+ {
+ m_line_buffer.append(1, static_cast<const char>(*m_cursor));
+ }
+ }
+
+ // append n characters to make sure that there is sufficient
+ // space between m_cursor and m_limit
+ m_line_buffer.append(1, '\x00');
+ m_line_buffer.append(n - 1, '\x01');
+ }
+ else
+ {
+ // delete processed characters from line buffer
+ m_line_buffer.erase(0, static_cast<size_t>(offset_start));
+ // read next line from input stream
+ std::string line;
+ std::getline(*m_stream, line, '\n');
+ // add line with newline symbol to the line buffer
+ m_line_buffer += line + "\n";
+ }
+
+ // set pointers
+ m_content = reinterpret_cast<const lexer_char_t*>(m_line_buffer.c_str());
+ assert(m_content != nullptr);
+ m_start = m_content;
+ m_marker = m_start + offset_marker;
+ m_cursor = m_start + offset_cursor;
+ m_limit = m_start + m_line_buffer.size();
+ }
+
+ /// return string representation of last read token
+ string_t get_token_string() const
+ {
+ assert(m_start != nullptr);
+ return string_t(reinterpret_cast<typename string_t::const_pointer>(m_start),
+ static_cast<size_t>(m_cursor - m_start));
+ }
+
+ /*!
+ @brief return string value for string tokens
+
+ The function iterates the characters between the opening and closing
+ quotes of the string value. The complete string is the range
+ [m_start,m_cursor). Consequently, we iterate from m_start+1 to
+ m_cursor-1.
+
+ We differentiate two cases:
+
+ 1. Escaped characters. In this case, a new character is constructed
+ according to the nature of the escape. Some escapes create new
+ characters (e.g., `"\\n"` is replaced by `"\n"`), some are copied
+ as is (e.g., `"\\\\"`). Furthermore, Unicode escapes of the shape
+ `"\\uxxxx"` need special care. In this case, to_unicode takes care
+ of the construction of the values.
+ 2. Unescaped characters are copied as is.
+
+ @pre `m_cursor - m_start >= 2`, meaning the length of the last token
+ is at least 2 bytes which is trivially true for any string (which
+ consists of at least two quotes).
+
+ " c1 c2 c3 ... "
+ ^ ^
+ m_start m_cursor
+
+ @complexity Linear in the length of the string.\n
+
+ Lemma: The loop body will always terminate.\n
+
+ Proof (by contradiction): Assume the loop body does not terminate. As
+ the loop body does not contain another loop, one of the called
+ functions must never return. The called functions are `std::strtoul`
+ and to_unicode. Neither function can loop forever, so the loop body
+ will never loop forever which contradicts the assumption that the loop
+ body does not terminate, q.e.d.\n
+
+ Lemma: The loop condition for the for loop is eventually false.\n
+
+ Proof (by contradiction): Assume the loop does not terminate. Due to
+ the above lemma, this can only be due to a tautological loop
+ condition; that is, the loop condition i < m_cursor - 1 must always be
+ true. Let x be the change of i for any loop iteration. Then
+ m_start + 1 + x < m_cursor - 1 must hold to loop indefinitely. This
+ can be rephrased to m_cursor - m_start - 2 > x. With the
+ precondition, we x <= 0, meaning that the loop condition holds
+ indefinitly if i is always decreased. However, observe that the value
+ of i is strictly increasing with each iteration, as it is incremented
+ by 1 in the iteration expression and never decremented inside the loop
+ body. Hence, the loop condition will eventually be false which
+ contradicts the assumption that the loop condition is a tautology,
+ q.e.d.
+
+ @return string value of current token without opening and closing
+ quotes
+ @throw std::out_of_range if to_unicode fails
+ */
+ string_t get_string() const
+ {
+ assert(m_cursor - m_start >= 2);
+
+ string_t result;
+ result.reserve(static_cast<size_t>(m_cursor - m_start - 2));
+
+ // iterate the result between the quotes
+ for (const lexer_char_t* i = m_start + 1; i < m_cursor - 1; ++i)
+ {
+ // process escaped characters
+ if (*i == '\\')
+ {
+ // read next character
+ ++i;
+
+ switch (*i)
+ {
+ // the default escapes
+ case 't':
+ {
+ result += "\t";
+ break;
+ }
+ case 'b':
+ {
+ result += "\b";
+ break;
+ }
+ case 'f':
+ {
+ result += "\f";
+ break;
+ }
+ case 'n':
+ {
+ result += "\n";
+ break;
+ }
+ case 'r':
+ {
+ result += "\r";
+ break;
+ }
+ case '\\':
+ {
+ result += "\\";
+ break;
+ }
+ case '/':
+ {
+ result += "/";
+ break;
+ }
+ case '"':
+ {
+ result += "\"";
+ break;
+ }
+
+ // unicode
+ case 'u':
+ {
+ // get code xxxx from uxxxx
+ auto codepoint = std::strtoul(std::string(reinterpret_cast<typename string_t::const_pointer>(i + 1),
+ 4).c_str(), nullptr, 16);
+
+ // check if codepoint is a high surrogate
+ if (codepoint >= 0xD800 and codepoint <= 0xDBFF)
+ {
+ // make sure there is a subsequent unicode
+ if ((i + 6 >= m_limit) or * (i + 5) != '\\' or * (i + 6) != 'u')
+ {
+ throw std::invalid_argument("missing low surrogate");
+ }
+
+ // get code yyyy from uxxxx\uyyyy
+ auto codepoint2 = std::strtoul(std::string(reinterpret_cast<typename string_t::const_pointer>
+ (i + 7), 4).c_str(), nullptr, 16);
+ result += to_unicode(codepoint, codepoint2);
+ // skip the next 10 characters (xxxx\uyyyy)
+ i += 10;
+ }
+ else if (codepoint >= 0xDC00 and codepoint <= 0xDFFF)
+ {
+ // we found a lone low surrogate
+ throw std::invalid_argument("missing high surrogate");
+ }
+ else
+ {
+ // add unicode character(s)
+ result += to_unicode(codepoint);
+ // skip the next four characters (xxxx)
+ i += 4;
+ }
+ break;
+ }
+ }
+ }
+ else
+ {
+ // all other characters are just copied to the end of the
+ // string
+ result.append(1, static_cast<typename string_t::value_type>(*i));
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief parse floating point number
+
+ This function (and its overloads) serves to select the most approprate
+ standard floating point number parsing function based on the type
+ supplied via the first parameter. Set this to @a
+ static_cast<number_float_t*>(nullptr).
+
+ @param[in] type the @ref number_float_t in use
+
+ @param[in,out] endptr recieves a pointer to the first character after
+ the number
+
+ @return the floating point number
+ */
+ long double str_to_float_t(long double* /* type */, char** endptr) const
+ {
+ return std::strtold(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
+ }
+
+ /*!
+ @brief parse floating point number
+
+ This function (and its overloads) serves to select the most approprate
+ standard floating point number parsing function based on the type
+ supplied via the first parameter. Set this to @a
+ static_cast<number_float_t*>(nullptr).
+
+ @param[in] type the @ref number_float_t in use
+
+ @param[in,out] endptr recieves a pointer to the first character after
+ the number
+
+ @return the floating point number
+ */
+ double str_to_float_t(double* /* type */, char** endptr) const
+ {
+ return std::strtod(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
+ }
+
+ /*!
+ @brief parse floating point number
+
+ This function (and its overloads) serves to select the most approprate
+ standard floating point number parsing function based on the type
+ supplied via the first parameter. Set this to @a
+ static_cast<number_float_t*>(nullptr).
+
+ @param[in] type the @ref number_float_t in use
+
+ @param[in,out] endptr recieves a pointer to the first character after
+ the number
+
+ @return the floating point number
+ */
+ float str_to_float_t(float* /* type */, char** endptr) const
+ {
+ return std::strtof(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr);
+ }
+
+ /*!
+ @brief return number value for number tokens
+
+ This function translates the last token into the most appropriate
+ number type (either integer, unsigned integer or floating point),
+ which is passed back to the caller via the result parameter.
+
+ This function parses the integer component up to the radix point or
+ exponent while collecting information about the 'floating point
+ representation', which it stores in the result parameter. If there is
+ no radix point or exponent, and the number can fit into a @ref
+ number_integer_t or @ref number_unsigned_t then it sets the result
+ parameter accordingly.
+
+ If the number is a floating point number the number is then parsed
+ using @a std:strtod (or @a std:strtof or @a std::strtold).
+
+ @param[out] result @ref basic_json object to receive the number, or
+ NAN if the conversion read past the current token. The latter case
+ needs to be treated by the caller function.
+ */
+ void get_number(basic_json& result) const
+ {
+ assert(m_start != nullptr);
+
+ const lexer::lexer_char_t* curptr = m_start;
+
+ // accumulate the integer conversion result (unsigned for now)
+ number_unsigned_t value = 0;
+
+ // maximum absolute value of the relevant integer type
+ number_unsigned_t max;
+
+ // temporarily store the type to avoid unecessary bitfield access
+ value_t type;
+
+ // look for sign
+ if (*curptr == '-')
+ {
+ type = value_t::number_integer;
+ max = static_cast<uint64_t>((std::numeric_limits<number_integer_t>::max)()) + 1;
+ curptr++;
+ }
+ else
+ {
+ type = value_t::number_unsigned;
+ max = static_cast<uint64_t>((std::numeric_limits<number_unsigned_t>::max)());
+ }
+
+ // count the significant figures
+ for (; curptr < m_cursor; curptr++)
+ {
+ // quickly skip tests if a digit
+ if (*curptr < '0' || *curptr > '9')
+ {
+ if (*curptr == '.')
+ {
+ // don't count '.' but change to float
+ type = value_t::number_float;
+ continue;
+ }
+ // assume exponent (if not then will fail parse): change to
+ // float, stop counting and record exponent details
+ type = value_t::number_float;
+ break;
+ }
+
+ // skip if definitely not an integer
+ if (type != value_t::number_float)
+ {
+ // multiply last value by ten and add the new digit
+ auto temp = value * 10 + *curptr - '0';
+
+ // test for overflow
+ if (temp < value || temp > max)
+ {
+ // overflow
+ type = value_t::number_float;
+ }
+ else
+ {
+ // no overflow - save it
+ value = temp;
+ }
+ }
+ }
+
+ // save the value (if not a float)
+ if (type == value_t::number_unsigned)
+ {
+ result.m_value.number_unsigned = value;
+ }
+ else if (type == value_t::number_integer)
+ {
+ result.m_value.number_integer = -static_cast<number_integer_t>(value);
+ }
+ else
+ {
+ // parse with strtod
+ result.m_value.number_float = str_to_float_t(static_cast<number_float_t*>(nullptr), NULL);
+
+ // replace infinity and NAN by null
+ if (not std::isfinite(result.m_value.number_float))
+ {
+ type = value_t::null;
+ result.m_value = basic_json::json_value();
+ }
+ }
+
+ // save the type
+ result.m_type = type;
+ }
+
+ private:
+ /// optional input stream
+ std::istream* m_stream = nullptr;
+ /// line buffer buffer for m_stream
+ string_t m_line_buffer {};
+ /// the buffer pointer
+ const lexer_char_t* m_content = nullptr;
+ /// pointer to the beginning of the current symbol
+ const lexer_char_t* m_start = nullptr;
+ /// pointer for backtracking information
+ const lexer_char_t* m_marker = nullptr;
+ /// pointer to the current symbol
+ const lexer_char_t* m_cursor = nullptr;
+ /// pointer to the end of the buffer
+ const lexer_char_t* m_limit = nullptr;
+ /// the last token type
+ token_type last_token_type = token_type::end_of_input;
+ };
+
+ /*!
+ @brief syntax analysis
+
+ This class implements a recursive decent parser.
+ */
+ class parser
+ {
+ public:
+ /// a parser reading from a string literal
+ parser(const char* buff, const parser_callback_t cb = nullptr)
+ : callback(cb),
+ m_lexer(reinterpret_cast<const typename lexer::lexer_char_t*>(buff), strlen(buff))
+ {}
+
+ /// a parser reading from an input stream
+ parser(std::istream& is, const parser_callback_t cb = nullptr)
+ : callback(cb), m_lexer(is)
+ {}
+
+ /// a parser reading from an iterator range with contiguous storage
+ template<class IteratorType, typename std::enable_if<
+ std::is_same<typename std::iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value
+ , int>::type
+ = 0>
+ parser(IteratorType first, IteratorType last, const parser_callback_t cb = nullptr)
+ : callback(cb),
+ m_lexer(reinterpret_cast<const typename lexer::lexer_char_t*>(&(*first)),
+ static_cast<size_t>(std::distance(first, last)))
+ {}
+
+ /// public parser interface
+ basic_json parse()
+ {
+ // read first token
+ get_token();
+
+ basic_json result = parse_internal(true);
+ result.assert_invariant();
+
+ expect(lexer::token_type::end_of_input);
+
+ // return parser result and replace it with null in case the
+ // top-level value was discarded by the callback function
+ return result.is_discarded() ? basic_json() : std::move(result);
+ }
+
+ private:
+ /// the actual parser
+ basic_json parse_internal(bool keep)
+ {
+ auto result = basic_json(value_t::discarded);
+
+ switch (last_token)
+ {
+ case lexer::token_type::begin_object:
+ {
+ if (keep and (not callback
+ or ((keep = callback(depth++, parse_event_t::object_start, result)) != 0)))
+ {
+ // explicitly set result to object to cope with {}
+ result.m_type = value_t::object;
+ result.m_value = value_t::object;
+ }
+
+ // read next token
+ get_token();
+
+ // closing } -> we are done
+ if (last_token == lexer::token_type::end_object)
+ {
+ get_token();
+ if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ {
+ result = basic_json(value_t::discarded);
+ }
+ return result;
+ }
+
+ // no comma is expected here
+ unexpect(lexer::token_type::value_separator);
+
+ // otherwise: parse key-value pairs
+ do
+ {
+ // ugly, but could be fixed with loop reorganization
+ if (last_token == lexer::token_type::value_separator)
+ {
+ get_token();
+ }
+
+ // store key
+ expect(lexer::token_type::value_string);
+ const auto key = m_lexer.get_string();
+
+ bool keep_tag = false;
+ if (keep)
+ {
+ if (callback)
+ {
+ basic_json k(key);
+ keep_tag = callback(depth, parse_event_t::key, k);
+ }
+ else
+ {
+ keep_tag = true;
+ }
+ }
+
+ // parse separator (:)
+ get_token();
+ expect(lexer::token_type::name_separator);
+
+ // parse and add value
+ get_token();
+ auto value = parse_internal(keep);
+ if (keep and keep_tag and not value.is_discarded())
+ {
+ result[key] = std::move(value);
+ }
+ }
+ while (last_token == lexer::token_type::value_separator);
+
+ // closing }
+ expect(lexer::token_type::end_object);
+ get_token();
+ if (keep and callback and not callback(--depth, parse_event_t::object_end, result))
+ {
+ result = basic_json(value_t::discarded);
+ }
+
+ return result;
+ }
+
+ case lexer::token_type::begin_array:
+ {
+ if (keep and (not callback
+ or ((keep = callback(depth++, parse_event_t::array_start, result)) != 0)))
+ {
+ // explicitly set result to object to cope with []
+ result.m_type = value_t::array;
+ result.m_value = value_t::array;
+ }
+
+ // read next token
+ get_token();
+
+ // closing ] -> we are done
+ if (last_token == lexer::token_type::end_array)
+ {
+ get_token();
+ if (callback and not callback(--depth, parse_event_t::array_end, result))
+ {
+ result = basic_json(value_t::discarded);
+ }
+ return result;
+ }
+
+ // no comma is expected here
+ unexpect(lexer::token_type::value_separator);
+
+ // otherwise: parse values
+ do
+ {
+ // ugly, but could be fixed with loop reorganization
+ if (last_token == lexer::token_type::value_separator)
+ {
+ get_token();
+ }
+
+ // parse value
+ auto value = parse_internal(keep);
+ if (keep and not value.is_discarded())
+ {
+ result.push_back(std::move(value));
+ }
+ }
+ while (last_token == lexer::token_type::value_separator);
+
+ // closing ]
+ expect(lexer::token_type::end_array);
+ get_token();
+ if (keep and callback and not callback(--depth, parse_event_t::array_end, result))
+ {
+ result = basic_json(value_t::discarded);
+ }
+
+ return result;
+ }
+
+ case lexer::token_type::literal_null:
+ {
+ get_token();
+ result.m_type = value_t::null;
+ break;
+ }
+
+ case lexer::token_type::value_string:
+ {
+ const auto s = m_lexer.get_string();
+ get_token();
+ result = basic_json(s);
+ break;
+ }
+
+ case lexer::token_type::literal_true:
+ {
+ get_token();
+ result.m_type = value_t::boolean;
+ result.m_value = true;
+ break;
+ }
+
+ case lexer::token_type::literal_false:
+ {
+ get_token();
+ result.m_type = value_t::boolean;
+ result.m_value = false;
+ break;
+ }
+
+ case lexer::token_type::value_number:
+ {
+ m_lexer.get_number(result);
+ get_token();
+ break;
+ }
+
+ default:
+ {
+ // the last token was unexpected
+ unexpect(last_token);
+ }
+ }
+
+ if (keep and callback and not callback(depth, parse_event_t::value, result))
+ {
+ result = basic_json(value_t::discarded);
+ }
+ return result;
+ }
+
+ /// get next token from lexer
+ typename lexer::token_type get_token()
+ {
+ last_token = m_lexer.scan();
+ return last_token;
+ }
+
+ void expect(typename lexer::token_type t) const
+ {
+ if (t != last_token)
+ {
+ std::string error_msg = "parse error - unexpected ";
+ error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token_string() +
+ "'") :
+ lexer::token_type_name(last_token));
+ error_msg += "; expected " + lexer::token_type_name(t);
+ throw std::invalid_argument(error_msg);
+ }
+ }
+
+ void unexpect(typename lexer::token_type t) const
+ {
+ if (t == last_token)
+ {
+ std::string error_msg = "parse error - unexpected ";
+ error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token_string() +
+ "'") :
+ lexer::token_type_name(last_token));
+ throw std::invalid_argument(error_msg);
+ }
+ }
+
+ private:
+ /// current level of recursion
+ int depth = 0;
+ /// callback function
+ const parser_callback_t callback = nullptr;
+ /// the type of the last read token
+ typename lexer::token_type last_token = lexer::token_type::uninitialized;
+ /// the lexer
+ lexer m_lexer;
+ };
+
+ public:
+ /*!
+ @brief JSON Pointer
+
+ A JSON pointer defines a string syntax for identifying a specific value
+ within a JSON document. It can be used with functions `at` and
+ `operator[]`. Furthermore, JSON pointers are the base for JSON patches.
+
+ @sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
+
+ @since version 2.0.0
+ */
+ class json_pointer
+ {
+ /// allow basic_json to access private members
+ friend class basic_json;
+
+ public:
+ /*!
+ @brief create JSON pointer
+
+ Create a JSON pointer according to the syntax described in
+ [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3).
+
+ @param[in] s string representing the JSON pointer; if omitted, the
+ empty string is assumed which references the whole JSON
+ value
+
+ @throw std::domain_error if reference token is nonempty and does not
+ begin with a slash (`/`); example: `"JSON pointer must be empty or
+ begin with /"`
+ @throw std::domain_error if a tilde (`~`) is not followed by `0`
+ (representing `~`) or `1` (representing `/`); example: `"escape error:
+ ~ must be followed with 0 or 1"`
+
+ @liveexample{The example shows the construction several valid JSON
+ pointers as well as the exceptional behavior.,json_pointer}
+
+ @since version 2.0.0
+ */
+ explicit json_pointer(const std::string& s = "")
+ : reference_tokens(split(s))
+ {}
+
+ /*!
+ @brief return a string representation of the JSON pointer
+
+ @invariant For each JSON pointer `ptr`, it holds:
+ @code {.cpp}
+ ptr == json_pointer(ptr.to_string());
+ @endcode
+
+ @return a string representation of the JSON pointer
+
+ @liveexample{The example shows the result of `to_string`.,
+ json_pointer__to_string}
+
+ @since version 2.0.0
+ */
+ std::string to_string() const noexcept
+ {
+ return std::accumulate(reference_tokens.begin(),
+ reference_tokens.end(), std::string{},
+ [](const std::string & a, const std::string & b)
+ {
+ return a + "/" + escape(b);
+ });
+ }
+
+ /// @copydoc to_string()
+ operator std::string() const
+ {
+ return to_string();
+ }
+
+ private:
+ /// remove and return last reference pointer
+ std::string pop_back()
+ {
+ if (is_root())
+ {
+ throw std::domain_error("JSON pointer has no parent");
+ }
+
+ auto last = reference_tokens.back();
+ reference_tokens.pop_back();
+ return last;
+ }
+
+ /// return whether pointer points to the root document
+ bool is_root() const
+ {
+ return reference_tokens.empty();
+ }
+
+ json_pointer top() const
+ {
+ if (is_root())
+ {
+ throw std::domain_error("JSON pointer has no parent");
+ }
+
+ json_pointer result = *this;
+ result.reference_tokens = {reference_tokens[0]};
+ return result;
+ }
+
+ /*!
+ @brief create and return a reference to the pointed to value
+
+ @complexity Linear in the number of reference tokens.
+ */
+ reference get_and_create(reference j) const
+ {
+ pointer result = &j;
+
+ // in case no reference tokens exist, return a reference to the
+ // JSON value j which will be overwritten by a primitive value
+ for (const auto& reference_token : reference_tokens)
+ {
+ switch (result->m_type)
+ {
+ case value_t::null:
+ {
+ if (reference_token == "0")
+ {
+ // start a new array if reference token is 0
+ result = &result->operator[](0);
+ }
+ else
+ {
+ // start a new object otherwise
+ result = &result->operator[](reference_token);
+ }
+ break;
+ }
+
+ case value_t::object:
+ {
+ // create an entry in the object
+ result = &result->operator[](reference_token);
+ break;
+ }
+
+ case value_t::array:
+ {
+ // create an entry in the array
+ result = &result->operator[](static_cast<size_type>(std::stoi(reference_token)));
+ break;
+ }
+
+ /*
+ The following code is only reached if there exists a
+ reference token _and_ the current value is primitive. In
+ this case, we have an error situation, because primitive
+ values may only occur as single value; that is, with an
+ empty list of reference tokens.
+ */
+ default:
+ {
+ throw std::domain_error("invalid value to unflatten");
+ }
+ }
+ }
+
+ return *result;
+ }
+
+ /*!
+ @brief return a reference to the pointed to value
+
+ @note This version does not throw if a value is not present, but tries
+ to create nested values instead. For instance, calling this function
+ with pointer `"/this/that"` on a null value is equivalent to calling
+ `operator[]("this").operator[]("that")` on that value, effectively
+ changing the null value to an object.
+
+ @param[in] ptr a JSON value
+
+ @return reference to the JSON value pointed to by the JSON pointer
+
+ @complexity Linear in the length of the JSON pointer.
+
+ @throw std::out_of_range if the JSON pointer can not be resolved
+ @throw std::domain_error if an array index begins with '0'
+ @throw std::invalid_argument if an array index was not a number
+ */
+ reference get_unchecked(pointer ptr) const
+ {
+ for (const auto& reference_token : reference_tokens)
+ {
+ // convert null values to arrays or objects before continuing
+ if (ptr->m_type == value_t::null)
+ {
+ // check if reference token is a number
+ const bool nums = std::all_of(reference_token.begin(),
+ reference_token.end(),
+ [](const char x)
+ {
+ return std::isdigit(x);
+ });
+
+ // change value to array for numbers or "-" or to object
+ // otherwise
+ if (nums or reference_token == "-")
+ {
+ *ptr = value_t::array;
+ }
+ else
+ {
+ *ptr = value_t::object;
+ }
+ }
+
+ switch (ptr->m_type)
+ {
+ case value_t::object:
+ {
+ // use unchecked object access
+ ptr = &ptr->operator[](reference_token);
+ break;
+ }
+
+ case value_t::array:
+ {
+ // error condition (cf. RFC 6901, Sect. 4)
+ if (reference_token.size() > 1 and reference_token[0] == '0')
+ {
+ throw std::domain_error("array index must not begin with '0'");
+ }
+
+ if (reference_token == "-")
+ {
+ // explicityly treat "-" as index beyond the end
+ ptr = &ptr->operator[](ptr->m_value.array->size());
+ }
+ else
+ {
+ // convert array index to number; unchecked access
+ ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
+ }
+ break;
+ }
+
+ default:
+ {
+ throw std::out_of_range("unresolved reference token '" + reference_token + "'");
+ }
+ }
+ }
+
+ return *ptr;
+ }
+
+ reference get_checked(pointer ptr) const
+ {
+ for (const auto& reference_token : reference_tokens)
+ {
+ switch (ptr->m_type)
+ {
+ case value_t::object:
+ {
+ // note: at performs range check
+ ptr = &ptr->at(reference_token);
+ break;
+ }
+
+ case value_t::array:
+ {
+ if (reference_token == "-")
+ {
+ // "-" always fails the range check
+ throw std::out_of_range("array index '-' (" +
+ std::to_string(ptr->m_value.array->size()) +
+ ") is out of range");
+ }
+
+ // error condition (cf. RFC 6901, Sect. 4)
+ if (reference_token.size() > 1 and reference_token[0] == '0')
+ {
+ throw std::domain_error("array index must not begin with '0'");
+ }
+
+ // note: at performs range check
+ ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
+ break;
+ }
+
+ default:
+ {
+ throw std::out_of_range("unresolved reference token '" + reference_token + "'");
+ }
+ }
+ }
+
+ return *ptr;
+ }
+
+ /*!
+ @brief return a const reference to the pointed to value
+
+ @param[in] ptr a JSON value
+
+ @return const reference to the JSON value pointed to by the JSON
+ pointer
+ */
+ const_reference get_unchecked(const_pointer ptr) const
+ {
+ for (const auto& reference_token : reference_tokens)
+ {
+ switch (ptr->m_type)
+ {
+ case value_t::object:
+ {
+ // use unchecked object access
+ ptr = &ptr->operator[](reference_token);
+ break;
+ }
+
+ case value_t::array:
+ {
+ if (reference_token == "-")
+ {
+ // "-" cannot be used for const access
+ throw std::out_of_range("array index '-' (" +
+ std::to_string(ptr->m_value.array->size()) +
+ ") is out of range");
+ }
+
+ // error condition (cf. RFC 6901, Sect. 4)
+ if (reference_token.size() > 1 and reference_token[0] == '0')
+ {
+ throw std::domain_error("array index must not begin with '0'");
+ }
+
+ // use unchecked array access
+ ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token)));
+ break;
+ }
+
+ default:
+ {
+ throw std::out_of_range("unresolved reference token '" + reference_token + "'");
+ }
+ }
+ }
+
+ return *ptr;
+ }
+
+ const_reference get_checked(const_pointer ptr) const
+ {
+ for (const auto& reference_token : reference_tokens)
+ {
+ switch (ptr->m_type)
+ {
+ case value_t::object:
+ {
+ // note: at performs range check
+ ptr = &ptr->at(reference_token);
+ break;
+ }
+
+ case value_t::array:
+ {
+ if (reference_token == "-")
+ {
+ // "-" always fails the range check
+ throw std::out_of_range("array index '-' (" +
+ std::to_string(ptr->m_value.array->size()) +
+ ") is out of range");
+ }
+
+ // error condition (cf. RFC 6901, Sect. 4)
+ if (reference_token.size() > 1 and reference_token[0] == '0')
+ {
+ throw std::domain_error("array index must not begin with '0'");
+ }
+
+ // note: at performs range check
+ ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token)));
+ break;
+ }
+
+ default:
+ {
+ throw std::out_of_range("unresolved reference token '" + reference_token + "'");
+ }
+ }
+ }
+
+ return *ptr;
+ }
+
+ /// split the string input to reference tokens
+ static std::vector<std::string> split(const std::string& reference_string)
+ {
+ std::vector<std::string> result;
+
+ // special case: empty reference string -> no reference tokens
+ if (reference_string.empty())
+ {
+ return result;
+ }
+
+ // check if nonempty reference string begins with slash
+ if (reference_string[0] != '/')
+ {
+ throw std::domain_error("JSON pointer must be empty or begin with '/'");
+ }
+
+ // extract the reference tokens:
+ // - slash: position of the last read slash (or end of string)
+ // - start: position after the previous slash
+ for (
+ // search for the first slash after the first character
+ size_t slash = reference_string.find_first_of("/", 1),
+ // set the beginning of the first reference token
+ start = 1;
+ // we can stop if start == string::npos+1 = 0
+ start != 0;
+ // set the beginning of the next reference token
+ // (will eventually be 0 if slash == std::string::npos)
+ start = slash + 1,
+ // find next slash
+ slash = reference_string.find_first_of("/", start))
+ {
+ // use the text between the beginning of the reference token
+ // (start) and the last slash (slash).
+ auto reference_token = reference_string.substr(start, slash - start);
+
+ // check reference tokens are properly escaped
+ for (size_t pos = reference_token.find_first_of("~");
+ pos != std::string::npos;
+ pos = reference_token.find_first_of("~", pos + 1))
+ {
+ assert(reference_token[pos] == '~');
+
+ // ~ must be followed by 0 or 1
+ if (pos == reference_token.size() - 1 or
+ (reference_token[pos + 1] != '0' and
+ reference_token[pos + 1] != '1'))
+ {
+ throw std::domain_error("escape error: '~' must be followed with '0' or '1'");
+ }
+ }
+
+ // finally, store the reference token
+ unescape(reference_token);
+ result.push_back(reference_token);
+ }
+
+ return result;
+ }
+
+ private:
+ /*!
+ @brief replace all occurrences of a substring by another string
+
+ @param[in,out] s the string to manipulate
+ @param[in] f the substring to replace with @a t
+ @param[in] t the string to replace @a f
+
+ @return The string @a s where all occurrences of @a f are replaced
+ with @a t.
+
+ @pre The search string @a f must not be empty.
+
+ @since version 2.0.0
+ */
+ static void replace_substring(std::string& s,
+ const std::string& f,
+ const std::string& t)
+ {
+ assert(not f.empty());
+
+ for (
+ size_t pos = s.find(f); // find first occurrence of f
+ pos != std::string::npos; // make sure f was found
+ s.replace(pos, f.size(), t), // replace with t
+ pos = s.find(f, pos + t.size()) // find next occurrence of f
+ );
+ }
+
+ /// escape tilde and slash
+ static std::string escape(std::string s)
+ {
+ // escape "~"" to "~0" and "/" to "~1"
+ replace_substring(s, "~", "~0");
+ replace_substring(s, "/", "~1");
+ return s;
+ }
+
+ /// unescape tilde and slash
+ static void unescape(std::string& s)
+ {
+ // first transform any occurrence of the sequence '~1' to '/'
+ replace_substring(s, "~1", "/");
+ // then transform any occurrence of the sequence '~0' to '~'
+ replace_substring(s, "~0", "~");
+ }
+
+ /*!
+ @param[in] reference_string the reference string to the current value
+ @param[in] value the value to consider
+ @param[in,out] result the result object to insert values to
+
+ @note Empty objects or arrays are flattened to `null`.
+ */
+ static void flatten(const std::string& reference_string,
+ const basic_json& value,
+ basic_json& result)
+ {
+ switch (value.m_type)
+ {
+ case value_t::array:
+ {
+ if (value.m_value.array->empty())
+ {
+ // flatten empty array as null
+ result[reference_string] = nullptr;
+ }
+ else
+ {
+ // iterate array and use index as reference string
+ for (size_t i = 0; i < value.m_value.array->size(); ++i)
+ {
+ flatten(reference_string + "/" + std::to_string(i),
+ value.m_value.array->operator[](i), result);
+ }
+ }
+ break;
+ }
+
+ case value_t::object:
+ {
+ if (value.m_value.object->empty())
+ {
+ // flatten empty object as null
+ result[reference_string] = nullptr;
+ }
+ else
+ {
+ // iterate object and use keys as reference string
+ for (const auto& element : *value.m_value.object)
+ {
+ flatten(reference_string + "/" + escape(element.first),
+ element.second, result);
+ }
+ }
+ break;
+ }
+
+ default:
+ {
+ // add primitive value with its reference string
+ result[reference_string] = value;
+ break;
+ }
+ }
+ }
+
+ /*!
+ @param[in] value flattened JSON
+
+ @return unflattened JSON
+ */
+ static basic_json unflatten(const basic_json& value)
+ {
+ if (not value.is_object())
+ {
+ throw std::domain_error("only objects can be unflattened");
+ }
+
+ basic_json result;
+
+ // iterate the JSON object values
+ for (const auto& element : *value.m_value.object)
+ {
+ if (not element.second.is_primitive())
+ {
+ throw std::domain_error("values in object must be primitive");
+ }
+
+ // assign value to reference pointed to by JSON pointer; Note
+ // that if the JSON pointer is "" (i.e., points to the whole
+ // value), function get_and_create returns a reference to
+ // result itself. An assignment will then create a primitive
+ // value.
+ json_pointer(element.first).get_and_create(result) = element.second;
+ }
+
+ return result;
+ }
+
+ private:
+ /// the reference tokens
+ std::vector<std::string> reference_tokens {};
+ };
+
+ //////////////////////////
+ // JSON Pointer support //
+ //////////////////////////
+
+ /// @name JSON Pointer functions
+ /// @{
+
+ /*!
+ @brief access specified element via JSON Pointer
+
+ Uses a JSON pointer to retrieve a reference to the respective JSON value.
+ No bound checking is performed. Similar to @ref operator[](const typename
+ object_t::key_type&), `null` values are created in arrays and objects if
+ necessary.
+
+ In particular:
+ - If the JSON pointer points to an object key that does not exist, it
+ is created an filled with a `null` value before a reference to it
+ is returned.
+ - If the JSON pointer points to an array index that does not exist, it
+ is created an filled with a `null` value before a reference to it
+ is returned. All indices between the current maximum and the given
+ index are also filled with `null`.
+ - The special value `-` is treated as a synonym for the index past the
+ end.
+
+ @param[in] ptr a JSON pointer
+
+ @return reference to the element pointed to by @a ptr
+
+ @complexity Constant.
+
+ @throw std::out_of_range if the JSON pointer can not be resolved
+ @throw std::domain_error if an array index begins with '0'
+ @throw std::invalid_argument if an array index was not a number
+
+ @liveexample{The behavior is shown in the example.,operatorjson_pointer}
+
+ @since version 2.0.0
+ */
+ reference operator[](const json_pointer& ptr)
+ {
+ return ptr.get_unchecked(this);
+ }
+
+ /*!
+ @brief access specified element via JSON Pointer
+
+ Uses a JSON pointer to retrieve a reference to the respective JSON value.
+ No bound checking is performed. The function does not change the JSON
+ value; no `null` values are created. In particular, the the special value
+ `-` yields an exception.
+
+ @param[in] ptr JSON pointer to the desired element
+
+ @return const reference to the element pointed to by @a ptr
+
+ @complexity Constant.
+
+ @throw std::out_of_range if the JSON pointer can not be resolved
+ @throw std::domain_error if an array index begins with '0'
+ @throw std::invalid_argument if an array index was not a number
+
+ @liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
+
+ @since version 2.0.0
+ */
+ const_reference operator[](const json_pointer& ptr) const
+ {
+ return ptr.get_unchecked(this);
+ }
+
+ /*!
+ @brief access specified element via JSON Pointer
+
+ Returns a reference to the element at with specified JSON pointer @a ptr,
+ with bounds checking.
+
+ @param[in] ptr JSON pointer to the desired element
+
+ @return reference to the element pointed to by @a ptr
+
+ @complexity Constant.
+
+ @throw std::out_of_range if the JSON pointer can not be resolved
+ @throw std::domain_error if an array index begins with '0'
+ @throw std::invalid_argument if an array index was not a number
+
+ @liveexample{The behavior is shown in the example.,at_json_pointer}
+
+ @since version 2.0.0
+ */
+ reference at(const json_pointer& ptr)
+ {
+ return ptr.get_checked(this);
+ }
+
+ /*!
+ @brief access specified element via JSON Pointer
+
+ Returns a const reference to the element at with specified JSON pointer @a
+ ptr, with bounds checking.
+
+ @param[in] ptr JSON pointer to the desired element
+
+ @return reference to the element pointed to by @a ptr
+
+ @complexity Constant.
+
+ @throw std::out_of_range if the JSON pointer can not be resolved
+ @throw std::domain_error if an array index begins with '0'
+ @throw std::invalid_argument if an array index was not a number
+
+ @liveexample{The behavior is shown in the example.,at_json_pointer_const}
+
+ @since version 2.0.0
+ */
+ const_reference at(const json_pointer& ptr) const
+ {
+ return ptr.get_checked(this);
+ }
+
+ /*!
+ @brief return flattened JSON value
+
+ The function creates a JSON object whose keys are JSON pointers (see [RFC
+ 6901](https://tools.ietf.org/html/rfc6901)) and whose values are all
+ primitive. The original JSON value can be restored using the @ref
+ unflatten() function.
+
+ @return an object that maps JSON pointers to primitve values
+
+ @note Empty objects and arrays are flattened to `null` and will not be
+ reconstructed correctly by the @ref unflatten() function.
+
+ @complexity Linear in the size the JSON value.
+
+ @liveexample{The following code shows how a JSON object is flattened to an
+ object whose keys consist of JSON pointers.,flatten}
+
+ @sa @ref unflatten() for the reverse function
+
+ @since version 2.0.0
+ */
+ basic_json flatten() const
+ {
+ basic_json result(value_t::object);
+ json_pointer::flatten("", *this, result);
+ return result;
+ }
+
+ /*!
+ @brief unflatten a previously flattened JSON value
+
+ The function restores the arbitrary nesting of a JSON value that has been
+ flattened before using the @ref flatten() function. The JSON value must
+ meet certain constraints:
+ 1. The value must be an object.
+ 2. The keys must be JSON pointers (see
+ [RFC 6901](https://tools.ietf.org/html/rfc6901))
+ 3. The mapped values must be primitive JSON types.
+
+ @return the original JSON from a flattened version
+
+ @note Empty objects and arrays are flattened by @ref flatten() to `null`
+ values and can not unflattened to their original type. Apart from
+ this example, for a JSON value `j`, the following is always true:
+ `j == j.flatten().unflatten()`.
+
+ @complexity Linear in the size the JSON value.
+
+ @liveexample{The following code shows how a flattened JSON object is
+ unflattened into the original nested JSON object.,unflatten}
+
+ @sa @ref flatten() for the reverse function
+
+ @since version 2.0.0
+ */
+ basic_json unflatten() const
+ {
+ return json_pointer::unflatten(*this);
+ }
+
+ /// @}
+
+ //////////////////////////
+ // JSON Patch functions //
+ //////////////////////////
+
+ /// @name JSON Patch functions
+ /// @{
+
+ /*!
+ @brief applies a JSON patch
+
+ [JSON Patch](http://jsonpatch.com) defines a JSON document structure for
+ expressing a sequence of operations to apply to a JSON) document. With
+ this funcion, a JSON Patch is applied to the current JSON value by
+ executing all operations from the patch.
+
+ @param[in] json_patch JSON patch document
+ @return patched document
+
+ @note The application of a patch is atomic: Either all operations succeed
+ and the patched document is returned or an exception is thrown. In
+ any case, the original value is not changed: the patch is applied
+ to a copy of the value.
+
+ @throw std::out_of_range if a JSON pointer inside the patch could not
+ be resolved successfully in the current JSON value; example: `"key baz
+ not found"`
+ @throw invalid_argument if the JSON patch is malformed (e.g., mandatory
+ attributes are missing); example: `"operation add must have member path"`
+
+ @complexity Linear in the size of the JSON value and the length of the
+ JSON patch. As usually only a fraction of the JSON value is affected by
+ the patch, the complexity can usually be neglected.
+
+ @liveexample{The following code shows how a JSON patch is applied to a
+ value.,patch}
+
+ @sa @ref diff -- create a JSON patch by comparing two JSON values
+
+ @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
+ @sa [RFC 6901 (JSON Pointer)](https://tools.ietf.org/html/rfc6901)
+
+ @since version 2.0.0
+ */
+ basic_json patch(const basic_json& json_patch) const
+ {
+ // make a working copy to apply the patch to
+ basic_json result = *this;
+
+ // the valid JSON Patch operations
+ enum class patch_operations {add, remove, replace, move, copy, test, invalid};
+
+ const auto get_op = [](const std::string op)
+ {
+ if (op == "add")
+ {
+ return patch_operations::add;
+ }
+ if (op == "remove")
+ {
+ return patch_operations::remove;
+ }
+ if (op == "replace")
+ {
+ return patch_operations::replace;
+ }
+ if (op == "move")
+ {
+ return patch_operations::move;
+ }
+ if (op == "copy")
+ {
+ return patch_operations::copy;
+ }
+ if (op == "test")
+ {
+ return patch_operations::test;
+ }
+
+ return patch_operations::invalid;
+ };
+
+ // wrapper for "add" operation; add value at ptr
+ const auto operation_add = [&result](json_pointer & ptr, basic_json val)
+ {
+ // adding to the root of the target document means replacing it
+ if (ptr.is_root())
+ {
+ result = val;
+ }
+ else
+ {
+ // make sure the top element of the pointer exists
+ json_pointer top_pointer = ptr.top();
+ if (top_pointer != ptr)
+ {
+ result.at(top_pointer);
+ }
+
+ // get reference to parent of JSON pointer ptr
+ const auto last_path = ptr.pop_back();
+ basic_json& parent = result[ptr];
+
+ switch (parent.m_type)
+ {
+ case value_t::null:
+ case value_t::object:
+ {
+ // use operator[] to add value
+ parent[last_path] = val;
+ break;
+ }
+
+ case value_t::array:
+ {
+ if (last_path == "-")
+ {
+ // special case: append to back
+ parent.push_back(val);
+ }
+ else
+ {
+ const auto idx = std::stoi(last_path);
+ if (static_cast<size_type>(idx) > parent.size())
+ {
+ // avoid undefined behavior
+ throw std::out_of_range("array index " + std::to_string(idx) + " is out of range");
+ }
+ else
+ {
+ // default case: insert add offset
+ parent.insert(parent.begin() + static_cast<difference_type>(idx), val);
+ }
+ }
+ break;
+ }
+
+ default:
+ {
+ // if there exists a parent it cannot be primitive
+ assert(false); // LCOV_EXCL_LINE
+ }
+ }
+ }
+ };
+
+ // wrapper for "remove" operation; remove value at ptr
+ const auto operation_remove = [&result](json_pointer & ptr)
+ {
+ // get reference to parent of JSON pointer ptr
+ const auto last_path = ptr.pop_back();
+ basic_json& parent = result.at(ptr);
+
+ // remove child
+ if (parent.is_object())
+ {
+ // perform range check
+ auto it = parent.find(last_path);
+ if (it != parent.end())
+ {
+ parent.erase(it);
+ }
+ else
+ {
+ throw std::out_of_range("key '" + last_path + "' not found");
+ }
+ }
+ else if (parent.is_array())
+ {
+ // note erase performs range check
+ parent.erase(static_cast<size_type>(std::stoi(last_path)));
+ }
+ };
+
+ // type check
+ if (not json_patch.is_array())
+ {
+ // a JSON patch must be an array of objects
+ throw std::invalid_argument("JSON patch must be an array of objects");
+ }
+
+ // iterate and apply th eoperations
+ for (const auto& val : json_patch)
+ {
+ // wrapper to get a value for an operation
+ const auto get_value = [&val](const std::string & op,
+ const std::string & member,
+ bool string_type) -> basic_json&
+ {
+ // find value
+ auto it = val.m_value.object->find(member);
+
+ // context-sensitive error message
+ const auto error_msg = (op == "op") ? "operation" : "operation '" + op + "'";
+
+ // check if desired value is present
+ if (it == val.m_value.object->end())
+ {
+ throw std::invalid_argument(error_msg + " must have member '" + member + "'");
+ }
+
+ // check if result is of type string
+ if (string_type and not it->second.is_string())
+ {
+ throw std::invalid_argument(error_msg + " must have string member '" + member + "'");
+ }
+
+ // no error: return value
+ return it->second;
+ };
+
+ // type check
+ if (not val.is_object())
+ {
+ throw std::invalid_argument("JSON patch must be an array of objects");
+ }
+
+ // collect mandatory members
+ const std::string op = get_value("op", "op", true);
+ const std::string path = get_value(op, "path", true);
+ json_pointer ptr(path);
+
+ switch (get_op(op))
+ {
+ case patch_operations::add:
+ {
+ operation_add(ptr, get_value("add", "value", false));
+ break;
+ }
+
+ case patch_operations::remove:
+ {
+ operation_remove(ptr);
+ break;
+ }
+
+ case patch_operations::replace:
+ {
+ // the "path" location must exist - use at()
+ result.at(ptr) = get_value("replace", "value", false);
+ break;
+ }
+
+ case patch_operations::move:
+ {
+ const std::string from_path = get_value("move", "from", true);
+ json_pointer from_ptr(from_path);
+
+ // the "from" location must exist - use at()
+ basic_json v = result.at(from_ptr);
+
+ // The move operation is functionally identical to a
+ // "remove" operation on the "from" location, followed
+ // immediately by an "add" operation at the target
+ // location with the value that was just removed.
+ operation_remove(from_ptr);
+ operation_add(ptr, v);
+ break;
+ }
+
+ case patch_operations::copy:
+ {
+ const std::string from_path = get_value("copy", "from", true);;
+ const json_pointer from_ptr(from_path);
+
+ // the "from" location must exist - use at()
+ result[ptr] = result.at(from_ptr);
+ break;
+ }
+
+ case patch_operations::test:
+ {
+ bool success = false;
+ try
+ {
+ // check if "value" matches the one at "path"
+ // the "path" location must exist - use at()
+ success = (result.at(ptr) == get_value("test", "value", false));
+ }
+ catch (std::out_of_range&)
+ {
+ // ignore out of range errors: success remains false
+ }
+
+ // throw an exception if test fails
+ if (not success)
+ {
+ throw std::domain_error("unsuccessful: " + val.dump());
+ }
+
+ break;
+ }
+
+ case patch_operations::invalid:
+ {
+ // op must be "add", "remove", "replace", "move", "copy", or
+ // "test"
+ throw std::invalid_argument("operation value '" + op + "' is invalid");
+ }
+ }
+ }
+
+ return result;
+ }
+
+ /*!
+ @brief creates a diff as a JSON patch
+
+ Creates a [JSON Patch](http://jsonpatch.com) so that value @a source can
+ be changed into the value @a target by calling @ref patch function.
+
+ @invariant For two JSON values @a source and @a target, the following code
+ yields always `true`:
+ @code {.cpp}
+ source.patch(diff(source, target)) == target;
+ @endcode
+
+ @note Currently, only `remove`, `add`, and `replace` operations are
+ generated.
+
+ @param[in] source JSON value to copare from
+ @param[in] target JSON value to copare against
+ @param[in] path helper value to create JSON pointers
+
+ @return a JSON patch to convert the @a source to @a target
+
+ @complexity Linear in the lengths of @a source and @a target.
+
+ @liveexample{The following code shows how a JSON patch is created as a
+ diff for two JSON values.,diff}
+
+ @sa @ref patch -- apply a JSON patch
+
+ @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
+
+ @since version 2.0.0
+ */
+ static basic_json diff(const basic_json& source,
+ const basic_json& target,
+ const std::string& path = "")
+ {
+ // the patch
+ basic_json result(value_t::array);
+
+ // if the values are the same, return empty patch
+ if (source == target)
+ {
+ return result;
+ }
+
+ if (source.type() != target.type())
+ {
+ // different types: replace value
+ result.push_back(
+ {
+ {"op", "replace"},
+ {"path", path},
+ {"value", target}
+ });
+ }
+ else
+ {
+ switch (source.type())
+ {
+ case value_t::array:
+ {
+ // first pass: traverse common elements
+ size_t i = 0;
+ while (i < source.size() and i < target.size())
+ {
+ // recursive call to compare array values at index i
+ auto temp_diff = diff(source[i], target[i], path + "/" + std::to_string(i));
+ result.insert(result.end(), temp_diff.begin(), temp_diff.end());
+ ++i;
+ }
+
+ // i now reached the end of at least one array
+ // in a second pass, traverse the remaining elements
+
+ // remove my remaining elements
+ const auto end_index = static_cast<difference_type>(result.size());
+ while (i < source.size())
+ {
+ // add operations in reverse order to avoid invalid
+ // indices
+ result.insert(result.begin() + end_index, object(
+ {
+ {"op", "remove"},
+ {"path", path + "/" + std::to_string(i)}
+ }));
+ ++i;
+ }
+
+ // add other remaining elements
+ while (i < target.size())
+ {
+ result.push_back(
+ {
+ {"op", "add"},
+ {"path", path + "/" + std::to_string(i)},
+ {"value", target[i]}
+ });
+ ++i;
+ }
+
+ break;
+ }
+
+ case value_t::object:
+ {
+ // first pass: traverse this object's elements
+ for (auto it = source.begin(); it != source.end(); ++it)
+ {
+ // escape the key name to be used in a JSON patch
+ const auto key = json_pointer::escape(it.key());
+
+ if (target.find(it.key()) != target.end())
+ {
+ // recursive call to compare object values at key it
+ auto temp_diff = diff(it.value(), target[it.key()], path + "/" + key);
+ result.insert(result.end(), temp_diff.begin(), temp_diff.end());
+ }
+ else
+ {
+ // found a key that is not in o -> remove it
+ result.push_back(object(
+ {
+ {"op", "remove"},
+ {"path", path + "/" + key}
+ }));
+ }
+ }
+
+ // second pass: traverse other object's elements
+ for (auto it = target.begin(); it != target.end(); ++it)
+ {
+ if (source.find(it.key()) == source.end())
+ {
+ // found a key that is not in this -> add it
+ const auto key = json_pointer::escape(it.key());
+ result.push_back(
+ {
+ {"op", "add"},
+ {"path", path + "/" + key},
+ {"value", it.value()}
+ });
+ }
+ }
+
+ break;
+ }
+
+ default:
+ {
+ // both primitive type: replace value
+ result.push_back(
+ {
+ {"op", "replace"},
+ {"path", path},
+ {"value", target}
+ });
+ break;
+ }
+ }
+ }
+
+ return result;
+ }
+
+ /// @}
+};
+
+
+/////////////
+// presets //
+/////////////
+
+/*!
+@brief default JSON class
+
+This type is the default specialization of the @ref basic_json class which
+uses the standard template types.
+
+@since version 1.0.0
+*/
+using json = basic_json<>;
+}
+
+
+///////////////////////
+// nonmember support //
+///////////////////////
+
+// specialization of std::swap, and std::hash
+namespace std
+{
+/*!
+@brief exchanges the values of two JSON objects
+
+@since version 1.0.0
+*/
+template<>
+inline void swap(nlohmann::json& j1,
+ nlohmann::json& j2) noexcept(
+ is_nothrow_move_constructible<nlohmann::json>::value and
+ is_nothrow_move_assignable<nlohmann::json>::value
+ )
+{
+ j1.swap(j2);
+}
+
+/// hash value for JSON objects
+template<>
+struct hash<nlohmann::json>
+{
+ /*!
+ @brief return a hash value for a JSON object
+
+ @since version 1.0.0
+ */
+ std::size_t operator()(const nlohmann::json& j) const
+ {
+ // a naive hashing via the string representation
+ const auto& h = hash<nlohmann::json::string_t>();
+ return h(j.dump());
+ }
+};
+}
+
+/*!
+@brief user-defined string literal for JSON values
+
+This operator implements a user-defined string literal for JSON objects. It
+can be used by adding `"_json"` to a string literal and returns a JSON object
+if no parse error occurred.
+
+@param[in] s a string representation of a JSON object
+@param[in] n the length of string @a s
+@return a JSON object
+
+@since version 1.0.0
+*/
+inline nlohmann::json operator "" _json(const char* s, std::size_t n)
+{
+ return nlohmann::json::parse(s, s + n);
+}
+
+/*!
+@brief user-defined string literal for JSON pointer
+
+This operator implements a user-defined string literal for JSON Pointers. It
+can be used by adding `"_json_pointer"` to a string literal and returns a JSON pointer
+object if no parse error occurred.
+
+@param[in] s a string representation of a JSON Pointer
+@param[in] n the length of string @a s
+@return a JSON pointer object
+
+@since version 2.0.0
+*/
+inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std::size_t n)
+{
+ return nlohmann::json::json_pointer(std::string(s, n));
+}
+
+// restore GCC/clang diagnostic settings
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+ #pragma GCC diagnostic pop
+#endif
+
+#endif
diff --git a/emu-radio/common-library/query.cc b/emu-radio/common-library/query.cc
new file mode 100644
index 00000000..890401fa
--- /dev/null
+++ b/emu-radio/common-library/query.cc
@@ -0,0 +1,219 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "query.h"
+
+const std::string QueryKeys::ACTION = "action";
+const std::string QueryKeys::OBJECT_NAME = "object_name";
+const std::string QueryKeys::FILTER = "filter";
+const std::string QueryKeys::PARAMS = "params";
+const std::string QueryKeys::FIELD_NAMES = "field_names";
+const std::string QueryKeys::LAST = "last";
+
+Query::Query ()
+ : query (Json::object ())
+{
+}
+
+Query::Query (const std::string &action, const std::string &objectName, const std::list<std::vector<std::string>> &filter, const std::map<std::string, std::string> &params, const std::list<std::string> &fields, bool last)
+{
+ this->action = action;
+ this->objectName = objectName;
+ this->filter = filter;
+ this->params = params;
+ this->fields = fields;
+ this->last = last;
+
+ if (fields.size () == 0)
+ {
+ this->fields.push_back ("*");
+ }
+
+ query[QueryKeys::ACTION] = action;
+ query[QueryKeys::OBJECT_NAME] = objectName;
+ query[QueryKeys::FILTER] = Json (filter);
+ query[QueryKeys::PARAMS] = Json (params);
+ query[QueryKeys::FIELD_NAMES] = Json (fields);
+ query[QueryKeys::LAST] = last;
+}
+
+Query Query::fromJsonString (const std::string &jsonString)
+{
+ Query query;
+ Json jsonQuery = Json::parse (jsonString);
+
+ std::cout << jsonQuery << std::endl;
+
+ std::cout << jsonQuery[QueryKeys::LAST] << std::endl;
+
+ query.setAction (jsonQuery[QueryKeys::ACTION]);
+ query.setLast (jsonQuery[QueryKeys::LAST]);
+ query.setObjectName (jsonQuery[QueryKeys::OBJECT_NAME]);
+
+ Json list = jsonQuery[QueryKeys::FIELD_NAMES];
+
+ for (Json::iterator it = list.begin (); it != list.end (); ++it)
+ {
+ query.fields.push_back (*it);
+ }
+
+ if (query.fields.size () == 0)
+ {
+ query.fields.push_back ("*");
+ }
+
+ Json list2 = jsonQuery[QueryKeys::FILTER];
+
+ for (Json::iterator it = list2.begin (); it != list2.end (); ++it)
+ {
+ query.filter.push_back (*it);
+ }
+
+ Json map = jsonQuery[QueryKeys::PARAMS];
+
+ for (Json::iterator it = map.begin (); it != map.end (); ++it)
+ {
+ std::cout << it.key () << " " << it.value ().dump () << std::endl;
+ query.params[it.key ()] = it.value ().dump ();
+ }
+
+ query.query[QueryKeys::ACTION] = query.action;
+ query.query[QueryKeys::OBJECT_NAME] = query.objectName;
+ query.query[QueryKeys::FILTER] = Json (query.filter);
+ query.query[QueryKeys::PARAMS] = Json (query.params);
+ query.query[QueryKeys::FIELD_NAMES] = Json (query.fields);
+ query.query[QueryKeys::LAST] = query.last;
+
+ return query;
+}
+
+void Query::removeQuotes (std::string &string)
+{
+ std::cout << string.front () << std::endl;
+ string.erase (remove (string.begin (), string.end (), '\"'), string.end ());
+}
+
+std::string Query::toJsonString (const Query &query)
+{
+ return query.query.dump ();
+}
+
+std::string
+Query::toJsonString (const std::string &action, const std::string &objectName, const std::list<std::vector<std::string>> &filter, const std::map<std::string, std::string> &params, const std::list<std::string> &fields, bool last)
+{
+ Json jsonQuery;
+
+ jsonQuery[QueryKeys::ACTION] = action;
+ jsonQuery[QueryKeys::OBJECT_NAME] = objectName;
+ jsonQuery[QueryKeys::FILTER] = Json (filter);
+ jsonQuery[QueryKeys::PARAMS] = Json (params);
+ jsonQuery[QueryKeys::FIELD_NAMES] = Json (fields);
+ jsonQuery[QueryKeys::LAST] = last;
+
+ return jsonQuery.dump ();
+}
+
+std::string Query::toJsonString ()
+{
+ return query.dump ();
+}
+
+const std::string &Query::getAction () const
+{
+ return action;
+}
+
+void Query::setAction (const std::string &action)
+{
+ Query::action = action;
+ removeQuotes (this->action);
+ query[QueryKeys::ACTION] = this->action;
+}
+
+const std::string &Query::getObjectName () const
+{
+ return objectName;
+}
+
+void Query::setObjectName (const std::string &objectName)
+{
+ Query::objectName = objectName;
+ removeQuotes (this->objectName);
+ query[QueryKeys::OBJECT_NAME] = this->objectName;
+}
+
+const std::list<std::vector<std::string>> &Query::getFilter () const
+{
+ return filter;
+}
+
+void Query::setFilter (const std::list<std::vector<std::string>> &filter)
+{
+ Query::filter = filter;
+
+ for (auto f : this->filter)
+ {
+ for (auto field : f)
+ {
+ removeQuotes (field);
+ }
+ }
+
+ query[QueryKeys::FILTER] = this->filter;
+}
+
+const std::map<std::string, std::string> &Query::getParams () const
+{
+ return params;
+}
+
+void Query::setParams (const std::map<std::string, std::string> &params)
+{
+ Query::params = params;
+ query[QueryKeys::PARAMS] = this->params;
+}
+
+const std::list<std::string> &Query::getFields () const
+{
+ return fields;
+}
+
+void Query::setFields (const std::list<std::string> &fields)
+{
+ Query::fields = fields;
+
+ for (auto field : this->fields)
+ {
+ removeQuotes (field);
+ }
+
+ query[QueryKeys::FIELD_NAMES] = this->fields;
+}
+
+bool Query::isLast () const
+{
+ return last;
+}
+
+void Query::setLast (int last)
+{
+ Query::last = last;
+ query[QueryKeys::LAST] = this->last;
+}
+
+bool Query::isEmpty ()
+{
+ return query.empty ();
+} \ No newline at end of file
diff --git a/emu-radio/common-library/query.h b/emu-radio/common-library/query.h
new file mode 100644
index 00000000..dad822c2
--- /dev/null
+++ b/emu-radio/common-library/query.h
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef WIFI_EMULATOR_QUERY_H
+#define WIFI_EMULATOR_QUERY_H
+
+#include <string>
+#include <list>
+#include <vector>
+#include <map>
+
+#include "json.h"
+
+typedef struct QueryKeys {
+ static const std::string ACTION;
+ static const std::string OBJECT_NAME;
+ static const std::string FILTER;
+ static const std::string PARAMS;
+ static const std::string FIELD_NAMES;
+ static const std::string LAST;
+} QueryKeys;
+
+// for convenience
+typedef nlohmann::json Json;
+
+class Query {
+ public:
+ Query ();
+
+ Query (const std::string &action, const std::string &objectName, const std::list<std::vector<std::string>> &filter, const std::map<std::string, std::string> &params, const std::list<std::string> &fields, bool last);
+
+ static Query fromJsonString (const std::string &jsonString);
+
+ static void removeQuotes (std::string &string);
+
+ static std::string toJsonString (const Query &query);
+
+ static std::string
+ toJsonString (const std::string &action, const std::string &objectName, const std::list<std::vector<std::string>> &filter, const std::map<std::string, std::string> &params, const std::list<std::string> &fields, bool last);
+
+ std::string toJsonString ();
+
+ const std::string &getAction () const;
+
+ void setAction (const std::string &action);
+
+ const std::string &getObjectName () const;
+
+ void setObjectName (const std::string &objectName);
+
+ const std::list<std::vector<std::string>> &getFilter () const;
+
+ void setFilter (const std::list<std::vector<std::string>> &filter);
+
+ const std::map<std::string, std::string> &getParams () const;
+
+ void setParams (const std::map<std::string, std::string> &params);
+
+ const std::list<std::string> &getFields () const;
+
+ void setFields (const std::list<std::string> &fields);
+
+ bool isLast () const;
+
+ void setLast (int last);
+
+ bool isEmpty ();
+
+ private:
+ Json query;
+
+ std::string action;
+ std::string objectName;
+ std::list<std::vector<std::string>> filter;
+ std::map<std::string, std::string> params;
+ std::list<std::string> fields;
+ bool last;
+};
+
+#endif //WIFI_EMULATOR_QUERY_H
diff --git a/emu-radio/common-library/tcp-server.cc b/emu-radio/common-library/tcp-server.cc
new file mode 100644
index 00000000..6b9129a1
--- /dev/null
+++ b/emu-radio/common-library/tcp-server.cc
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "tcp-server.h"
+
+TcpServer::TcpServer (unsigned short port, long read_timeout)
+ : port (port),
+ acceptor (io_service),
+ read_timeout (read_timeout)
+{
+}
+
+TcpServer::~TcpServer ()
+{
+}
+
+void TcpServer::setHandler (const HandlerFunction &handler)
+{
+ this->handler = handler;
+}
+
+void TcpServer::start ()
+{
+ if (io_service.stopped ())
+ io_service.reset ();
+
+ boost::asio::ip::tcp::endpoint endpoint;
+ endpoint = boost::asio::ip::tcp::endpoint (boost::asio::ip::tcp::v4 (), port);
+
+ acceptor.open (endpoint.protocol ());
+ acceptor.set_option (boost::asio::socket_base::reuse_address (true));
+ acceptor.bind (endpoint);
+ acceptor.listen ();
+
+ accept ();
+
+ //Set interrupt callbacks
+
+ boost::asio::io_service io_service;
+ boost::asio::signal_set signals (io_service, SIGINT, SIGQUIT);
+
+ signals.async_wait ([this] (const boost::system::error_code &errorCode, int)
+ {
+ std::cout << "Gracefully terminating tcp server" << std::endl;
+ this->io_service.reset ();
+ this->acceptor.cancel ();
+ });
+
+ io_service.run ();
+}
+
+void TcpServer::accept ()
+{
+ //Create new socket for this connection
+ //Shared_ptr is used to pass temporary objects to the asynchronous functions
+ std::shared_ptr <boost::asio::ip::tcp::socket> socket (new boost::asio::ip::tcp::socket (io_service));
+ acceptor.async_accept (*socket, [this, socket] (const boost::system::error_code &ec)
+ {
+ accept ();
+
+ if (ec)
+ {
+ if (ec == boost::asio::error::operation_aborted) // when the socket is closed by someone
+ return;
+ }
+
+ processIncomingData (socket);
+ });
+}
+
+void TcpServer::processIncomingData (std::shared_ptr <boost::asio::ip::tcp::socket> socket)
+{
+ // Set timeout on the following boost::asio::async-read or write function
+ std::shared_ptr <boost::asio::deadline_timer> timer;
+ if (read_timeout > 0)
+ timer = set_timeout_on_socket (socket, read_timeout);
+
+ std::shared_ptr <boost::asio::streambuf> buffer (new boost::asio::streambuf ());
+
+ boost::asio::async_read_until (*socket, *buffer, "\r\n\r\n", [this, timer, buffer, socket] (const boost::system::error_code &error, std::size_t bytes_transferred)
+ {
+ if (read_timeout > 0)
+ timer->cancel ();
+
+ if (error)
+ {
+ std::cerr << "Boost error code is not null! ERROR: " << error << std::endl;
+ return;
+ }
+
+ std::size_t bufferSize = buffer->size ();
+ buffer->commit (buffer->size ());
+ const uint8_t *data = boost::asio::buffer_cast<const uint8_t *> (buffer->data ());
+
+ std::string reply = handler (data, bufferSize);
+
+ if (reply != "")
+ {
+
+ boost::asio::async_write (*socket, boost::asio::buffer (reply.c_str (), reply
+ .size ()), [this] (boost::system::error_code ec, std::size_t /*length*/)
+ {
+ if (!ec)
+ {
+ std::cout << "Reply sent!" << std::endl;
+ }
+ else
+ {
+ std::cerr << "ERROR! Reply not sent." << std::endl;
+ }
+ });
+
+ }
+ });
+
+}
+
+std::shared_ptr <boost::asio::deadline_timer>
+TcpServer::set_timeout_on_socket (std::shared_ptr <boost::asio::ip::tcp::socket> socket, long seconds)
+{
+ std::shared_ptr <boost::asio::deadline_timer> timer (new boost::asio::deadline_timer (io_service));
+ timer->expires_from_now (boost::posix_time::seconds (seconds));
+ timer->async_wait ([socket] (const boost::system::error_code &ec)
+ {
+ if (!ec)
+ {
+ boost::system::error_code ec;
+ std::cout << "Connection timeout!" << std::endl;
+ socket->lowest_layer ().shutdown (boost::asio::ip::tcp::socket::shutdown_both, ec);
+ socket->lowest_layer ().close ();
+ }
+ });
+ return timer;
+} \ No newline at end of file
diff --git a/emu-radio/common-library/tcp-server.h b/emu-radio/common-library/tcp-server.h
new file mode 100644
index 00000000..3bffdf2a
--- /dev/null
+++ b/emu-radio/common-library/tcp-server.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef WIFI_EMULATOR_SERVER_H
+#define WIFI_EMULATOR_SERVER_H
+
+#include <functional>
+#include <boost/asio.hpp>
+#include <iostream>
+
+typedef std::function< std
+::string(
+const uint8_t*,
+std::size_t)>
+HandlerFunction;
+
+class TcpServer {
+ public:
+ explicit TcpServer (unsigned short port, long read_timeout = 5);
+
+ void setHandler (const HandlerFunction &handler);
+
+ ~TcpServer ();
+
+ void start ();
+
+ private:
+
+ void accept ();
+
+ void processIncomingData (std::shared_ptr <boost::asio::ip::tcp::socket> socket);
+
+ std::shared_ptr <boost::asio::deadline_timer>
+ set_timeout_on_socket (std::shared_ptr <boost::asio::ip::tcp::socket> socket, long seconds);
+
+ unsigned short port;
+ boost::asio::io_service io_service;
+ boost::asio::ip::tcp::acceptor acceptor;
+ long read_timeout;
+ HandlerFunction handler;
+};
+
+#endif //WIFI_EMULATOR_SERVER_H
diff --git a/emu-radio/common-library/websocket-server.cc b/emu-radio/common-library/websocket-server.cc
new file mode 100644
index 00000000..26a2cf76
--- /dev/null
+++ b/emu-radio/common-library/websocket-server.cc
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "websocket-server.h"
+
+WebSocketServer::WebSocketServer (unsigned short port)
+ : m_isRunning (false)
+{
+ try
+ {
+ // Initialize Asio
+ server.init_asio ();
+
+ // Set reuse address option
+ server.set_reuse_addr (true);
+
+ // Register our message handler
+ server.set_message_handler (bind (&WebSocketServer::onMessage, this, &server, ::_1, ::_2));
+
+ // Listen on port
+ server.listen (port);
+
+ }
+ catch (websocketpp::exception const &e)
+ {
+ std::cout << e.what () << std::endl;
+ }
+ catch (...)
+ {
+ std::cout << "Exception occurred.." << std::endl;
+ }
+}
+
+void WebSocketServer::setHandler (const HandlerFunction &handler)
+{
+ this->handler = handler;
+}
+
+void WebSocketServer::start ()
+{
+ m_isRunning = true;
+ int retries = 5;
+
+ while (m_isRunning && retries > 0)
+ {
+
+ try
+ {
+ // Start the server accept loop
+ server.start_accept ();
+
+ //Set interrupt callbacks
+
+ boost::asio::io_service io_service;
+ boost::asio::signal_set signals (server.get_io_service (), SIGINT, SIGQUIT);
+
+ signals.async_wait ([this] (const boost::system::error_code &errorCode, int)
+ {
+ std::cout << "Gracefully terminating websocket server" << std::endl;
+ this->m_isRunning = false;
+ this->server.stop ();
+ });
+
+ // Start the ASIO io_service run loop
+ server.run ();
+
+ }
+ catch (websocketpp::exception const &e)
+ {
+ std::cout << e.what () << std::endl;
+ }
+ catch (...)
+ {
+ std::cout << "Exception occurred.." << std::endl;
+ }
+
+ retries--;
+ }
+}
+
+void WebSocketServer::onMessage (Server *s, websocketpp::connection_hdl hdl, message_ptr msg)
+{
+ try
+ {
+ handler (s, hdl, msg, (uint8_t *) msg->get_payload ().c_str (), msg->get_payload ().size ());
+ }
+ catch (const websocketpp::lib::error_code &e)
+ {
+
+ std::cout << "Reply sent failed because: " << e << "(" << e.message () << ")" << std::endl;
+
+ }
+} \ No newline at end of file
diff --git a/emu-radio/common-library/websocket-server.h b/emu-radio/common-library/websocket-server.h
new file mode 100644
index 00000000..af664aef
--- /dev/null
+++ b/emu-radio/common-library/websocket-server.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef WIFI_EMULATOR_WEBSOCKETSERVER_H
+#define WIFI_EMULATOR_WEBSOCKETSERVER_H
+
+#include <websocketpp/config/asio_no_tls.hpp>
+#include <websocketpp/server.hpp>
+
+typedef websocketpp::server<websocketpp::config::asio> Server;
+typedef Server::message_ptr message_ptr;
+
+typedef std::function<void (Server *, websocketpp::connection_hdl, message_ptr, const uint8_t *, std::size_t)> HandlerFunction;
+
+using websocketpp::lib::placeholders::_1;
+using websocketpp::lib::placeholders::_2;
+using websocketpp::lib::bind;
+
+class WebSocketServer {
+ public:
+ explicit WebSocketServer (unsigned short port);
+
+ void setHandler (const HandlerFunction &handler);
+
+ ~WebSocketServer ()
+ {
+ };
+
+ void start ();
+
+ private:
+ void onMessage (Server *s, websocketpp::connection_hdl hdl, message_ptr msg);
+
+ Server server;
+
+ HandlerFunction handler;
+
+ volatile bool m_isRunning;
+};
+
+#endif //WIFI_EMULATOR_WEBSOCKETSERVER_H