json

json j2 = {
  {"pi", 3.141},
  {"happy", true},
  {"name", "Niels"},
  {"nothing", nullptr},
  {"answer", {
    {"everything", 42}
  }},
  {"list", {1, 0, 2}},
  {"object", {
    {"currency", "USD"},
    {"value", 42.99}
  }}
};

What happens if you mix a boolean with a map, add all kind of iterators and accessors and make it look like an STL-container? In the best case, you'll get what Niels Lohmann created during the last year.

Whenever you need to talk to JavaScript entities, or want to have some hierarchical, dynamic data structure, Niels' JSON implementation is willing to serve your needs. It needs no further explanation on how to deal with that library, since Niels has made a nice animated gif, linked in here:

JSON for Modern C++

My Use Cases

I am using that stuff to serialize master/detail data into a json structure, and push that into a sql database
json plays nicely together with msgpack so you can transport json in a binary-safe way over the network.
together with websocketpp, you can write websocket server-side code that is pushing into the browser's gui. This is being done as json, of course.

What I really like

header only, including parser, serialization
works as expected if you're familiar with stl containers (except currently array and object iterators, minor glitch)
comes with all bells and whistles you expect from an STL container (const reverse iterator needed? It's there)

What I don't like

Nothing, however, it would be cool to have a streaming parser here which can directly read from a stream (push, not pull).

Roman's Rating: 4.7 / 5

feature completeness: 5/5
architecture: 5/5
usability: 4/5
language integration: 5/5
dependencies: 5/5 (none)
build-system 5/5 (none)
documentation: 4/5 (good reference, good explanation of use cases and usage patterns)

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