json

a class for straightforward JSON manipulation

Linking

• put maxy/json.h, maxy/json.cpp into your project
• this requires certain code from maxy::strings (http://github.com/yekhlakov/strings), put all the files into maxy directory.
• #include "maxy/json.h" and enjoy
• see test.cpp for examples of the class usage

Notes

1. Parse

The class can parse std::strings and std::istreams, for example, auto j = json::parse ("[null, true, 0.3]"); The input may contain anything that can be a part of a json. Parser is quite relaxed, it ignores many violations of specification. Most notably, it allows for unquoted object keys and trailing commas. {a:"1",,,b:"2",} will therefore be parsed successfully.

2. Construct

The json may be constructed from ints, floats, bools, strings etc, producing atomic json values json s {"text"};.

Json objects may also be conveniently constructed, for example, json o {{ {"key1", json{"value1"}}, {"key2", json{666}}, {"key3", json{nullptr}} }}; produces a json {"key1":"value1","key2":666,"key3":null}.

3. Write

output_stream << j;

The object is written in strict format, i.e. no unnecessary whitespace, keys are quoted strings, no trailing comma.

4. Modify

j = 3; sets json to an integer value of 3 (floats, bools and strings are also accepted).

j["key"] = value; sets the "key" field of the object.

j["a"]["b"]["c"] = 42; we can construct nested objects just like that.

j[16] = nullptr; sets the array element.

Note that any assignment converts the json object into its appropriate type, losing any previous state.

json x = 16.0; // x is just 16.0

x.push_back(666); // x is an array [666]

x["a"] = false; // x is an object {"a":false}

x[0] = "123"; // x is an array ["123"]

5. Iterate

A json can be iterated over using range-for or begin()/end(). Atomary values can be iterated over too (as if they were containers with just one element).