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@@ -1,7 +0,0 @@
|
||||
json_unit
|
||||
json_benchmarks
|
||||
|
||||
working
|
||||
|
||||
html
|
||||
me.nlohmann.json.docset
|
||||
-58
@@ -1,58 +0,0 @@
|
||||
language: cpp
|
||||
|
||||
sudo: false
|
||||
|
||||
# from http://stackoverflow.com/a/32127147/266378
|
||||
matrix:
|
||||
include:
|
||||
- os: linux
|
||||
compiler: gcc
|
||||
addons:
|
||||
apt:
|
||||
sources: ['ubuntu-toolchain-r-test']
|
||||
packages: ['g++-4.9', 'valgrind', 'python-pip', 'python-yaml']
|
||||
before_script:
|
||||
- pip install --user git+git://github.com/eddyxu/cpp-coveralls.git
|
||||
after_success:
|
||||
- make clean
|
||||
- touch src/json.hpp
|
||||
- make json_unit CXXFLAGS="-fprofile-arcs -ftest-coverage -std=c++11 -lstdc++" CXX=$COMPILER
|
||||
- ./json_unit "*"
|
||||
- coveralls --exclude test/catch.hpp --exclude test/unit.cpp --include src/json.hpp --gcov-options '\-lp' --gcov 'gcov-4.9'
|
||||
env: COMPILER=g++-4.9
|
||||
|
||||
- os: linux
|
||||
compiler: gcc
|
||||
addons:
|
||||
apt:
|
||||
sources: ['ubuntu-toolchain-r-test']
|
||||
packages: ['g++-5', 'valgrind']
|
||||
env: COMPILER=g++-5
|
||||
|
||||
- os: linux
|
||||
compiler: clang
|
||||
addons:
|
||||
apt:
|
||||
sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.6']
|
||||
packages: ['clang-3.6', 'valgrind']
|
||||
env: COMPILER=clang++-3.6
|
||||
|
||||
- os: linux
|
||||
compiler: clang
|
||||
addons:
|
||||
apt:
|
||||
sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.7']
|
||||
packages: ['clang-3.7', 'valgrind']
|
||||
env: COMPILER=clang++-3.7
|
||||
|
||||
# - os: osx
|
||||
# compiler: clang
|
||||
# env: COMPILER=clang
|
||||
# before_install:
|
||||
# - brew update
|
||||
# - brew install valgrind
|
||||
|
||||
script:
|
||||
- make CXX=$COMPILER CXXFLAGS="-lstdc++"
|
||||
- ./json_unit "*"
|
||||
- valgrind --error-exitcode=1 --leak-check=full ./json_unit
|
||||
@@ -1,25 +0,0 @@
|
||||
cmake_minimum_required(VERSION 2.8)
|
||||
|
||||
project(json CXX)
|
||||
|
||||
add_executable(json_unit
|
||||
src/json.hpp test/catch.hpp test/unit.cpp
|
||||
)
|
||||
|
||||
if(MSVC)
|
||||
set(CMAKE_CXX_FLAGS
|
||||
"/EHsc"
|
||||
)
|
||||
|
||||
STRING(REPLACE "/O2" "/Od" CMAKE_CXX_FLAGS_RELEASE ${CMAKE_CXX_FLAGS_RELEASE})
|
||||
|
||||
add_definitions(-D_SCL_SECURE_NO_WARNINGS)
|
||||
else(MSVC)
|
||||
set(CMAKE_CXX_FLAGS
|
||||
"-std=c++11"
|
||||
)
|
||||
endif(MSVC)
|
||||
|
||||
include_directories(
|
||||
src test
|
||||
)
|
||||
@@ -1,78 +0,0 @@
|
||||
[](http://issuestats.com/github/nlohmann/json) [](http://issuestats.com/github/nlohmann/json)
|
||||
|
||||
# How to contribute
|
||||
|
||||
This project started as a little excuse to exercise some of the cool new C++11 features. Over time, people actually started to use the JSON library (yey!) and started to help improve it by proposing features, finding bugs, or even fixing my mistakes. I am really [thankful](https://github.com/nlohmann/json/blob/master/README.md#thanks) for this and try to keep track of all the helpers.
|
||||
|
||||
To make it as easy as possible for you to contribute and for me to keep an overview, here are a few guidelines which should help us avoid all kinds of unnecessary work or disappointment. And of course, this document is subject to discussion, so please [create an issue](https://github.com/nlohmann/json/issues/new) or a pull request if you find a way to improve it!
|
||||
|
||||
## Prerequisites
|
||||
|
||||
Please [create an issue](https://github.com/nlohmann/json/issues/new), assuming one does not already exist, and describe your concern. Note you need a [GitHub account](https://github.com/signup/free) for this.
|
||||
|
||||
If you want propose changes to the code, you need to download the [`re2c`](http://re2c.org) tool.
|
||||
|
||||
## Describe your issue
|
||||
|
||||
Clearly describe the issue:
|
||||
|
||||
- If it is a bug, please describe how to **reproduce** it. If possible, attach a complete example which demonstrates the error. Please also state what you **expected** to happen instead of the error.
|
||||
- If you propose a change or addition, try to give an **example** how the improved code could look like or how to use it.
|
||||
- If you found a compilation error, please tell us which **compiler** (version and operating system) you used and paste the (relevant part of) the error messages to the ticket.
|
||||
|
||||
## Files to change
|
||||
|
||||
There are currently two files which need to be edited:
|
||||
|
||||
1. [`src/json.hpp.re2c`](https://github.com/nlohmann/json/blob/master/src/json.hpp.re2c) (note the `.re2c` suffix) - This file contains a comment section which describes the JSON lexic. This section is translated by [`re2c`](http://re2c.org) into file [`src/json.hpp`](https://github.com/nlohmann/json/blob/master/src/json.hpp) which is plain "vanilla" C++11 code. (In fact, the generated lexer consists of some hundred lines of `goto`s, which is a hint you never want to edit this file...).
|
||||
|
||||
If you only edit file `src/json.hpp` (without the `.re2c` suffix), your changes will be overwritten as soon as the lexer is touched again. To generate the `src/json.hpp` file which is actually used during compilation of the tests and all other code, please execute
|
||||
|
||||
```sh
|
||||
make re2c
|
||||
```
|
||||
|
||||
To run [`re2c`](http://re2c.org) and generate/overwrite file `src/json.hpp` with your changes in file `src/json.hpp.re2c`.
|
||||
|
||||
|
||||
2. [`test/unit.cpp`](https://github.com/nlohmann/json/blob/master/test/unit.cpp) - This contains the [Catch](https://github.com/philsquared/Catch) unit tests which currently cover [100 %](https://coveralls.io/github/nlohmann/json) of the library's code.
|
||||
|
||||
If you add or change a feature, please also add a unit test to this file. The unit tests can be compiled with
|
||||
|
||||
```sh
|
||||
make
|
||||
```
|
||||
|
||||
and can be executed with
|
||||
|
||||
```sh
|
||||
./json_unit
|
||||
```
|
||||
|
||||
The test cases are also executed with several different compilers on [Travis](https://travis-ci.org/nlohmann/json) once you open a pull request.
|
||||
|
||||
Please understand that I cannot accept pull requests changing only file `src/json.hpp`.
|
||||
|
||||
|
||||
## Note
|
||||
|
||||
- If you open a pull request, the code will be automatically tested with [Valgrind](http://valgrind.org)'s Memcheck tool to detect memory leaks. Please be aware that the execution with Valgrind _may_ in rare cases yield different behavior than running the code directly. This can result in failing unit tests which run successfully without Valgrind.
|
||||
|
||||
## Please don't
|
||||
|
||||
- Only make changes to file `src/json.hpp` -- please read the paragraph above and understand why `src/json.hpp.re2c` exists.
|
||||
- The C++11 support varies between different **compilers** and versions. Please note the [list of supported compilers](https://github.com/nlohmann/json/blob/master/README.md#supported-compilers). Some compilers like GCC 4.8 (and earlier), Clang 3.3 (and earlier), or Microsoft Visual Studio 13.0 and earlier are known not to work due to missing or incomplete C++11 support. Please refrain from proposing changes that work around these compiler's limitations with `#ifdef`s or other means.
|
||||
- Specifically, I am aware of compilation problems with **Microsoft Visual Studio** (there even is an [issue label](https://github.com/nlohmann/json/issues?utf8=✓&q=label%3A%22visual+studio%22+) for these kind of bugs). I understand that even in 2016, complete C++11 support isn't there yet. But please also understand that I do not want to drop features or uglify the code just to make Microsoft's sub-standard compiler happy. The past has shown that there are ways to express the functionality such that the code compiles with the most recent MSVC - unfortunately, this is not the main objective of the project.
|
||||
- Please refrain from proposing changes that would **break [JSON](http://json.org) conformance**. If you propose a conformant extension of JSON to be supported by the library, please motivate this extension.
|
||||
- Please do not open pull requests that address **multiple issues**.
|
||||
|
||||
## Wanted
|
||||
|
||||
The following areas really need contribution:
|
||||
|
||||
- Getting the code to compile without errors with the latest **Microsoft Visual Studio** version. I am not using Windows, so I cannot debug code with MSVC myself. There is a job on [AppVeyor](https://ci.appveyor.com/project/nlohmann/json) though.
|
||||
- Extending the **continuous integration** beyond Linux running some versions of GCC and Clang on [Travis](https://travis-ci.org/nlohmann/json) and Microsoft Visual Studio on [AppVeyor](https://ci.appveyor.com/project/nlohmann/json). We have found a lot of bugs just because several compilers behave in a slightly different manner.
|
||||
- Improving the efficiency of the **JSON parser**. The current parser is implemented as a naive recursive descent parser with hand coded string handling. More sophisticated approaches like LALR parsers would be really appreciated. That said, parser generators like Bison or ANTLR do not play nice with single-header files -- I really would like to keep the parser inside the `json.hpp` header, and I am not aware of approaches similar to [`re2c`](http://re2c.org) for parsing.
|
||||
- Extending and updating existing **benchmarks** to include (the most recent version of) this library. Though efficiency is not everything, speed and memory consumption are very important characteristics for C++ developers, so having proper comparisons would be interesting.
|
||||
- Check the code with [**Coverity**](https://scan.coverity.com).
|
||||
- Make the code **locale-independent**. The library currently only works for a locale where `.` is the decimal point character.
|
||||
-22
@@ -1,22 +0,0 @@
|
||||
The library is licensed under the MIT License
|
||||
<http://opensource.org/licenses/MIT>:
|
||||
|
||||
Copyright (c) 2013-2016 Niels Lohmann
|
||||
|
||||
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.
|
||||
@@ -1,61 +0,0 @@
|
||||
.PHONY: pretty clean
|
||||
|
||||
# used programs
|
||||
RE2C = re2c
|
||||
SED = sed
|
||||
|
||||
# main target
|
||||
all: json_unit
|
||||
|
||||
# clean up
|
||||
clean:
|
||||
rm -f json_unit json_benchmarks
|
||||
|
||||
|
||||
##########################################################################
|
||||
# unit tests
|
||||
##########################################################################
|
||||
|
||||
# additional flags
|
||||
FLAGS = -Wall -Wextra -pedantic -Weffc++ -Wcast-align -Wcast-qual -Wctor-dtor-privacy -Wdisabled-optimization -Wformat=2 -Winit-self -Wmissing-declarations -Wmissing-include-dirs -Wold-style-cast -Woverloaded-virtual -Wredundant-decls -Wshadow -Wsign-conversion -Wsign-promo -Wstrict-overflow=5 -Wswitch -Wundef -Wno-unused -Wnon-virtual-dtor -Wreorder -Wdeprecated -Wfloat-equal
|
||||
|
||||
# build unit tests
|
||||
json_unit: test/unit.cpp src/json.hpp test/catch.hpp
|
||||
$(CXX) -std=c++11 $(CXXFLAGS) $(FLAGS) $(CPPFLAGS) -I src -I test $< $(LDFLAGS) -o $@
|
||||
|
||||
|
||||
##########################################################################
|
||||
# static analyzer
|
||||
##########################################################################
|
||||
|
||||
# call cppcheck on the main header file
|
||||
cppcheck:
|
||||
cppcheck --enable=all --inconclusive --std=c++11 src/json.hpp
|
||||
|
||||
|
||||
##########################################################################
|
||||
# maintainer targets
|
||||
##########################################################################
|
||||
|
||||
# create scanner with re2c
|
||||
re2c: src/json.hpp.re2c
|
||||
$(RE2C) -b -s -i --no-generation-date $< | $(SED) '1d' > src/json.hpp
|
||||
|
||||
# pretty printer
|
||||
pretty:
|
||||
astyle --style=allman --indent=spaces=4 --indent-modifiers \
|
||||
--indent-switches --indent-preproc-block --indent-preproc-define \
|
||||
--indent-col1-comments --pad-oper --pad-header --align-pointer=type \
|
||||
--align-reference=type --add-brackets --convert-tabs --close-templates \
|
||||
--lineend=linux --preserve-date --suffix=none \
|
||||
src/json.hpp src/json.hpp.re2c test/unit.cpp benchmarks/benchmarks.cpp doc/examples/*.cpp
|
||||
|
||||
|
||||
##########################################################################
|
||||
# benchmarks
|
||||
##########################################################################
|
||||
|
||||
# benchmarks
|
||||
json_benchmarks: benchmarks/benchmarks.cpp benchmarks/benchpress.hpp benchmarks/cxxopts.hpp src/json.hpp
|
||||
$(CXX) -std=c++11 $(CXXFLAGS) -O3 -flto -I src -I benchmarks $< $(LDFLAGS) -o $@
|
||||
./json_benchmarks
|
||||
@@ -1,413 +0,0 @@
|
||||

|
||||
|
||||
[](https://travis-ci.org/nlohmann/json)
|
||||
[](https://ci.appveyor.com/project/nlohmann/json)
|
||||
[](https://coveralls.io/r/nlohmann/json)
|
||||
[](http://melpon.org/wandbox/permlink/WSW3gHHE4UcZ9K3G)
|
||||
[](http://nlohmann.github.io/json)
|
||||
[](https://raw.githubusercontent.com/nlohmann/json/master/LICENSE.MIT)
|
||||
[](https://github.com/nlohmann/json/releases)
|
||||
[](http://github.com/nlohmann/json/issues)
|
||||
|
||||
## Design goals
|
||||
|
||||
There are myriads of [JSON](http://json.org) libraries out there, and each may even have its reason to exist. Our class had these design goals:
|
||||
|
||||
- **Intuitive syntax**. In languages such as Python, JSON feels like a first class data type. We used all the operator magic of modern C++ to achieve the same feeling in your code. Check out the [examples below](#examples) and you know, what I mean.
|
||||
|
||||
- **Trivial integration**. Our whole code consists of a single header file `json.hpp`. That's it. No library, no subproject, no dependencies, no complex build system. The class is written in vanilla C++11. All in all, everything should require no adjustment of your compiler flags or project settings.
|
||||
|
||||
- **Serious testing**. Our class is heavily [unit-tested](https://github.com/nlohmann/json/blob/master/test/json_unit.cc) and covers [100%](https://coveralls.io/r/nlohmann/json) of the code, including all exceptional behavior. Furthermore, we checked with [Valgrind](http://valgrind.org) that there are no memory leaks.
|
||||
|
||||
Other aspects were not so important to us:
|
||||
|
||||
- **Memory efficiency**. Each JSON object has an overhead of one pointer (the maximal size of a union) and one enumeration element (1 byte). The default generalization uses the following C++ data types: `std::string` for strings, `int64_t` or `double` for numbers, `std::map` for objects, `std::vector` for arrays, and `bool` for Booleans. However, you can template the generalized class `basic_json` to your needs.
|
||||
|
||||
- **Speed**. We currently implement the parser as naive [recursive descent parser](http://en.wikipedia.org/wiki/Recursive_descent_parser) with hand coded string handling. It is fast enough, but a [LALR-parser](http://en.wikipedia.org/wiki/LALR_parser) with a decent regular expression processor should be even faster (but would consist of more files which makes the integration harder).
|
||||
|
||||
See the [https://github.com/nlohmann/json/blob/master/CONTRIBUTING.md#please-dont](contribution guidelines) for more information.
|
||||
|
||||
## Integration
|
||||
|
||||
The single required source, file `json.hpp` is in the `src` directory or [released here](https://github.com/nlohmann/json/releases). All you need to do is add
|
||||
|
||||
```cpp
|
||||
#include "json.hpp"
|
||||
|
||||
// for convenience
|
||||
using json = nlohmann::json;
|
||||
```
|
||||
|
||||
to the files you want to use JSON objects. That's it. Do not forget to set the necessary switches to enable C++11 (e.g., `-std=c++11` for GCC and Clang).
|
||||
|
||||
## Supported compilers
|
||||
|
||||
Though it's 2016 already, the support for C++11 is still a bit sparse. Currently, the following compilers are known to work:
|
||||
|
||||
- GCC 4.9 - 6.0 (and possibly later)
|
||||
- Clang 3.4 - 3.8 (and possibly later)
|
||||
- Microsoft Visual C++ 14.0 RC (and possibly later)
|
||||
|
||||
I would be happy to learn about other compilers/versions.
|
||||
|
||||
For GCC running on MinGW or Android SDK, the error `'to_string' is not a member of 'std'` (or similarly, for `strtod`) may occur. Note this is not an issue with the code, but rather with the compiler itself. Please refer to [this site](http://tehsausage.com/mingw-to-string) and [this discussion](https://github.com/nlohmann/json/issues/136) for information on how to fix this bug.
|
||||
|
||||
|
||||
## Examples
|
||||
|
||||
Here are some examples to give you an idea how to use the class.
|
||||
|
||||
Assume you want to create the JSON object
|
||||
|
||||
```json
|
||||
{
|
||||
"pi": 3.141,
|
||||
"happy": true,
|
||||
"name": "Niels",
|
||||
"nothing": null,
|
||||
"answer": {
|
||||
"everything": 42
|
||||
},
|
||||
"list": [1, 0, 2],
|
||||
"object": {
|
||||
"currency": "USD",
|
||||
"value": 42.99
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
With the JSON class, you could write:
|
||||
|
||||
```cpp
|
||||
// create an empty structure (null)
|
||||
json j;
|
||||
|
||||
// add a number that is stored as double (note the implicit conversion of j to an object)
|
||||
j["pi"] = 3.141;
|
||||
|
||||
// add a Boolean that is stored as bool
|
||||
j["happy"] = true;
|
||||
|
||||
// add a string that is stored as std::string
|
||||
j["name"] = "Niels";
|
||||
|
||||
// add another null object by passing nullptr
|
||||
j["nothing"] = nullptr;
|
||||
|
||||
// add an object inside the object
|
||||
j["answer"]["everything"] = 42;
|
||||
|
||||
// add an array that is stored as std::vector (using an initializer list)
|
||||
j["list"] = { 1, 0, 2 };
|
||||
|
||||
// add another object (using an initializer list of pairs)
|
||||
j["object"] = { {"currency", "USD"}, {"value", 42.99} };
|
||||
|
||||
// instead, you could also write (which looks very similar to the JSON above)
|
||||
json j2 = {
|
||||
{"pi", 3.141},
|
||||
{"happy", true},
|
||||
{"name", "Niels"},
|
||||
{"nothing", nullptr},
|
||||
{"answer", {
|
||||
{"everything", 42}
|
||||
}},
|
||||
{"list", {1, 0, 2}},
|
||||
{"object", {
|
||||
{"currency", "USD"},
|
||||
{"value", 42.99}
|
||||
}}
|
||||
};
|
||||
```
|
||||
|
||||
Note that in all these cases, you never need to "tell" the compiler which JSON value you want to use. If you want to be explicit or express some edge cases, the functions `json::array` and `json::object` will help:
|
||||
|
||||
```cpp
|
||||
// a way to express the empty array []
|
||||
json empty_array_explicit = json::array();
|
||||
|
||||
// ways to express the empty object {}
|
||||
json empty_object_implicit = json({});
|
||||
json empty_object_explicit = json::object();
|
||||
|
||||
// a way to express an _array_ of key/value pairs [["currency", "USD"], ["value", 42.99]]
|
||||
json array_not_object = { json::array({"currency", "USD"}), json::array({"value", 42.99}) };
|
||||
```
|
||||
|
||||
### Serialization / Deserialization
|
||||
|
||||
You can create an object (deserialization) by appending `_json` to a string literal:
|
||||
|
||||
```cpp
|
||||
// create object from string literal
|
||||
json j = "{ \"happy\": true, \"pi\": 3.141 }"_json;
|
||||
|
||||
// or even nicer (thanks http://isocpp.org/blog/2015/01/json-for-modern-cpp)
|
||||
auto j2 = R"(
|
||||
{
|
||||
"happy": true,
|
||||
"pi": 3.141
|
||||
}
|
||||
)"_json;
|
||||
|
||||
// or explicitly
|
||||
auto j3 = json::parse("{ \"happy\": true, \"pi\": 3.141 }");
|
||||
```
|
||||
|
||||
You can also get a string representation (serialize):
|
||||
|
||||
```cpp
|
||||
// explicit conversion to string
|
||||
std::string s = j.dump(); // {\"happy\":true,\"pi\":3.141}
|
||||
|
||||
// serialization with pretty printing
|
||||
// pass in the amount of spaces to indent
|
||||
std::cout << j.dump(4) << std::endl;
|
||||
// {
|
||||
// "happy": true,
|
||||
// "pi": 3.141
|
||||
// }
|
||||
```
|
||||
|
||||
You can also use streams to serialize and deserialize:
|
||||
|
||||
```cpp
|
||||
// deserialize from standard input
|
||||
json j;
|
||||
std::cin >> j;
|
||||
|
||||
// serialize to standard output
|
||||
std::cout << j;
|
||||
|
||||
// the setw manipulator was overloaded to set the indentation for pretty printing
|
||||
std::cout << std::setw(4) << j << std::endl;
|
||||
```
|
||||
|
||||
These operators work for any subclasses of `std::istream` or `std::ostream`.
|
||||
|
||||
### STL-like access
|
||||
|
||||
We designed the JSON class to behave just like an STL container. In fact, it satisfies the [**ReversibleContainer**](http://en.cppreference.com/w/cpp/concept/ReversibleContainer) requirement.
|
||||
|
||||
```cpp
|
||||
// create an array using push_back
|
||||
json j;
|
||||
j.push_back("foo");
|
||||
j.push_back(1);
|
||||
j.push_back(true);
|
||||
|
||||
// iterate the array
|
||||
for (json::iterator it = j.begin(); it != j.end(); ++it) {
|
||||
std::cout << *it << '\n';
|
||||
}
|
||||
|
||||
// range-based for
|
||||
for (auto element : j) {
|
||||
std::cout << element << '\n';
|
||||
}
|
||||
|
||||
// getter/setter
|
||||
const std::string tmp = j[0];
|
||||
j[1] = 42;
|
||||
bool foo = j.at(2);
|
||||
|
||||
// other stuff
|
||||
j.size(); // 3 entries
|
||||
j.empty(); // false
|
||||
j.type(); // json::value_t::array
|
||||
j.clear(); // the array is empty again
|
||||
|
||||
// convenience type checkers
|
||||
j.is_null();
|
||||
j.is_boolean();
|
||||
j.is_number();
|
||||
j.is_object();
|
||||
j.is_array();
|
||||
j.is_string();
|
||||
|
||||
// comparison
|
||||
j == "[\"foo\", 1, true]"_json; // true
|
||||
|
||||
// create an object
|
||||
json o;
|
||||
o["foo"] = 23;
|
||||
o["bar"] = false;
|
||||
o["baz"] = 3.141;
|
||||
|
||||
// special iterator member functions for objects
|
||||
for (json::iterator it = o.begin(); it != o.end(); ++it) {
|
||||
std::cout << it.key() << " : " << it.value() << "\n";
|
||||
}
|
||||
|
||||
// find an entry
|
||||
if (o.find("foo") != o.end()) {
|
||||
// there is an entry with key "foo"
|
||||
}
|
||||
|
||||
// or simpler using count()
|
||||
int foo_present = o.count("foo"); // 1
|
||||
int fob_present = o.count("fob"); // 0
|
||||
|
||||
// delete an entry
|
||||
o.erase("foo");
|
||||
```
|
||||
|
||||
### Conversion from STL containers
|
||||
|
||||
Any sequence container (`std::array`, `std::vector`, `std::deque`, `std::forward_list`, `std::list`) whose values can be used to construct JSON types (e.g., integers, floating point numbers, Booleans, string types, or again STL containers described in this section) can be used to create a JSON array. The same holds for similar associative containers (`std::set`, `std::multiset`, `std::unordered_set`, `std::unordered_multiset`), but in these cases the order of the elements of the array depends how the elements are ordered in the respective STL container.
|
||||
|
||||
```cpp
|
||||
std::vector<int> c_vector {1, 2, 3, 4};
|
||||
json j_vec(c_vector);
|
||||
// [1, 2, 3, 4]
|
||||
|
||||
std::deque<double> c_deque {1.2, 2.3, 3.4, 5.6};
|
||||
json j_deque(c_deque);
|
||||
// [1.2, 2.3, 3.4, 5.6]
|
||||
|
||||
std::list<bool> c_list {true, true, false, true};
|
||||
json j_list(c_list);
|
||||
// [true, true, false, true]
|
||||
|
||||
std::forward_list<int64_t> c_flist {12345678909876, 23456789098765, 34567890987654, 45678909876543};
|
||||
json j_flist(c_flist);
|
||||
// [12345678909876, 23456789098765, 34567890987654, 45678909876543]
|
||||
|
||||
std::array<unsigned long, 4> c_array {{1, 2, 3, 4}};
|
||||
json j_array(c_array);
|
||||
// [1, 2, 3, 4]
|
||||
|
||||
std::set<std::string> c_set {"one", "two", "three", "four", "one"};
|
||||
json j_set(c_set); // only one entry for "one" is used
|
||||
// ["four", "one", "three", "two"]
|
||||
|
||||
std::unordered_set<std::string> c_uset {"one", "two", "three", "four", "one"};
|
||||
json j_uset(c_uset); // only one entry for "one" is used
|
||||
// maybe ["two", "three", "four", "one"]
|
||||
|
||||
std::multiset<std::string> c_mset {"one", "two", "one", "four"};
|
||||
json j_mset(c_mset); // only one entry for "one" is used
|
||||
// maybe ["one", "two", "four"]
|
||||
|
||||
std::unordered_multiset<std::string> c_umset {"one", "two", "one", "four"};
|
||||
json j_umset(c_umset); // both entries for "one" are used
|
||||
// maybe ["one", "two", "one", "four"]
|
||||
```
|
||||
|
||||
Likewise, any associative key-value containers (`std::map`, `std::multimap`, `std::unordered_map`, `std::unordered_multimap`) whose keys are can construct an `std::string` and whose values can be used to construct JSON types (see examples above) can be used to to create a JSON object. Note that in case of multimaps only one key is used in the JSON object and the value depends on the internal order of the STL container.
|
||||
|
||||
```cpp
|
||||
std::map<std::string, int> c_map { {"one", 1}, {"two", 2}, {"three", 3} };
|
||||
json j_map(c_map);
|
||||
// {"one": 1, "two": 2, "three": 3}
|
||||
|
||||
std::unordered_map<const char*, double> c_umap { {"one", 1.2}, {"two", 2.3}, {"three", 3.4} };
|
||||
json j_umap(c_umap);
|
||||
// {"one": 1.2, "two": 2.3, "three": 3.4}
|
||||
|
||||
std::multimap<std::string, bool> c_mmap { {"one", true}, {"two", true}, {"three", false}, {"three", true} };
|
||||
json j_mmap(c_mmap); // only one entry for key "three" is used
|
||||
// maybe {"one": true, "two": true, "three": true}
|
||||
|
||||
std::unordered_multimap<std::string, bool> c_ummap { {"one", true}, {"two", true}, {"three", false}, {"three", true} };
|
||||
json j_ummap(c_ummap); // only one entry for key "three" is used
|
||||
// maybe {"one": true, "two": true, "three": true}
|
||||
```
|
||||
|
||||
### Implicit conversions
|
||||
|
||||
The type of the JSON object is determined automatically by the expression to store. Likewise, the stored value is implicitly converted.
|
||||
|
||||
```cpp
|
||||
/// strings
|
||||
std::string s1 = "Hello, world!";
|
||||
json js = s1;
|
||||
std::string s2 = js;
|
||||
|
||||
// Booleans
|
||||
bool b1 = true;
|
||||
json jb = b1;
|
||||
bool b2 = jb;
|
||||
|
||||
// numbers
|
||||
int i = 42;
|
||||
json jn = i;
|
||||
double f = jn;
|
||||
|
||||
// etc.
|
||||
```
|
||||
|
||||
You can also explicitly ask for the value:
|
||||
|
||||
```cpp
|
||||
std::string vs = js.get<std::string>();
|
||||
bool vb = jb.get<bool>();
|
||||
int vi = jn.get<int>();
|
||||
|
||||
// etc.
|
||||
```
|
||||
|
||||
## License
|
||||
|
||||
<img align="right" src="http://opensource.org/trademarks/opensource/OSI-Approved-License-100x137.png">
|
||||
|
||||
The class is licensed under the [MIT License](http://opensource.org/licenses/MIT):
|
||||
|
||||
Copyright © 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.
|
||||
|
||||
## Thanks
|
||||
|
||||
I deeply appreciate the help of the following people.
|
||||
|
||||
- [Teemperor](https://github.com/Teemperor) implemented CMake support and lcov integration, realized escape and Unicode handling in the string parser, and fixed the JSON serialization.
|
||||
- [elliotgoodrich](https://github.com/elliotgoodrich) fixed an issue with double deletion in the iterator classes.
|
||||
- [kirkshoop](https://github.com/kirkshoop) made the iterators of the class composable to other libraries.
|
||||
- [wancw](https://github.com/wanwc) fixed a bug that hindered the class to compile with Clang.
|
||||
- Tomas Åblad found a bug in the iterator implementation.
|
||||
- [Joshua C. Randall](https://github.com/jrandall) fixed a bug in the floating-point serialization.
|
||||
- [Aaron Burghardt](https://github.com/aburgh) implemented code to parse streams incrementally. Furthermore, he greatly improved the parser class by allowing the definition of a filter function to discard undesired elements while parsing.
|
||||
- [Daniel Kopeček](https://github.com/dkopecek) fixed a bug in the compilation with GCC 5.0.
|
||||
- [Florian Weber](https://github.com/Florianjw) fixed a bug in and improved the performance of the comparison operators.
|
||||
- [Eric Cornelius](https://github.com/EricMCornelius) pointed out a bug in the handling with NaN and infinity values. He also improved the performance of the string escaping.
|
||||
- [易思龙](https://github.com/likebeta) implemented a conversion from anonymous enums.
|
||||
- [kepkin](https://github.com/kepkin) patiently pushed forward the support for Microsoft Visual studio.
|
||||
- [gregmarr](https://github.com/gregmarr) simplified the implementation of reverse iterators and helped with numerous hints and improvements.
|
||||
- [Caio Luppi](https://github.com/caiovlp) fixed a bug in the Unicode handling.
|
||||
- [dariomt](https://github.com/dariomt) fixed some typos in the examples.
|
||||
- [Daniel Frey](https://github.com/d-frey) cleaned up some pointers and implemented exception-safe memory allocation.
|
||||
- [Colin Hirsch](https://github.com/ColinH) took care of a small namespace issue.
|
||||
- [Huu Nguyen](https://github.com/whoshuu) correct a variable name in the documentation.
|
||||
- [Silverweed](https://github.com/silverweed) overloaded `parse()` to accept an rvalue reference.
|
||||
- [dariomt](https://github.com/dariomt) fixed a subtlety in MSVC type support and implemented the `get_ref()` function to get a reference to stored values.
|
||||
- [ZahlGraf](https://github.com/ZahlGraf) added a workaround that allows compilation using Android NDK.
|
||||
- [whackashoe](https://github.com/whackashoe) replaced a function that was marked as unsafe by Visual Studio.
|
||||
- [406345](https://github.com/406345) fixed two small warnings.
|
||||
- [Glen Fernandes](https://github.com/glenfe) noted a potential portability problem in the `has_mapped_type` function.
|
||||
- [Corbin Hughes](https://github.com/nibroc) fixed some typos in the contribution guidelines.
|
||||
- [twelsby](https://github.com/twelsby) fixed the array subscript operator, an issue that failed the MSVC build, and floating-point parsing/dumping.
|
||||
|
||||
Thanks a lot for helping out!
|
||||
|
||||
## Notes
|
||||
|
||||
- The code contains numerous debug assertions which can be switched off by defining the preprocessor macro `NDEBUG`, see the [documentation of `assert`](http://en.cppreference.com/w/cpp/error/assert).
|
||||
|
||||
## Execute unit tests
|
||||
|
||||
To compile and run the tests, you need to execute
|
||||
|
||||
```sh
|
||||
$ make
|
||||
$ ./json_unit "*"
|
||||
|
||||
===============================================================================
|
||||
All tests passed (3343329 assertions in 29 test cases)
|
||||
```
|
||||
|
||||
For more information, have a look at the file [.travis.yml](https://github.com/nlohmann/json/blob/master/.travis.yml).
|
||||
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@@ -0,0 +1,14 @@
|
||||
|
||||
<!doctype html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="utf-8">
|
||||
<title>Redirecting...</title>
|
||||
<link rel="canonical" href="../../operator_gtgt/">
|
||||
<script>var anchor=window.location.hash.substr(1);location.href="../../operator_gtgt/"+(anchor?"#"+anchor:"")</script>
|
||||
<meta http-equiv="refresh" content="0; url=../../operator_gtgt/">
|
||||
</head>
|
||||
<body>
|
||||
You're being redirected to a <a href="../../operator_gtgt/">new destination</a>.
|
||||
</body>
|
||||
</html>
|
||||
File diff suppressed because one or more lines are too long
@@ -0,0 +1,14 @@
|
||||
|
||||
<!doctype html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="utf-8">
|
||||
<title>Redirecting...</title>
|
||||
<link rel="canonical" href="../../operator_literal_json/">
|
||||
<script>var anchor=window.location.hash.substr(1);location.href="../../operator_literal_json/"+(anchor?"#"+anchor:"")</script>
|
||||
<meta http-equiv="refresh" content="0; url=../../operator_literal_json/">
|
||||
</head>
|
||||
<body>
|
||||
You're being redirected to a <a href="../../operator_literal_json/">new destination</a>.
|
||||
</body>
|
||||
</html>
|
||||
@@ -0,0 +1,14 @@
|
||||
|
||||
<!doctype html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="utf-8">
|
||||
<title>Redirecting...</title>
|
||||
<link rel="canonical" href="../../operator_literal_json_pointer/">
|
||||
<script>var anchor=window.location.hash.substr(1);location.href="../../operator_literal_json_pointer/"+(anchor?"#"+anchor:"")</script>
|
||||
<meta http-equiv="refresh" content="0; url=../../operator_literal_json_pointer/">
|
||||
</head>
|
||||
<body>
|
||||
You're being redirected to a <a href="../../operator_literal_json_pointer/">new destination</a>.
|
||||
</body>
|
||||
</html>
|
||||
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@@ -0,0 +1,14 @@
|
||||
|
||||
<!doctype html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="utf-8">
|
||||
<title>Redirecting...</title>
|
||||
<link rel="canonical" href="../../operator_ltlt/">
|
||||
<script>var anchor=window.location.hash.substr(1);location.href="../../operator_ltlt/"+(anchor?"#"+anchor:"")</script>
|
||||
<meta http-equiv="refresh" content="0; url=../../operator_ltlt/">
|
||||
</head>
|
||||
<body>
|
||||
You're being redirected to a <a href="../../operator_ltlt/">new destination</a>.
|
||||
</body>
|
||||
</html>
|
||||
File diff suppressed because one or more lines are too long
File diff suppressed because one or more lines are too long
File diff suppressed because one or more lines are too long
Some files were not shown because too many files have changed in this diff Show More
Reference in New Issue
Block a user