RapidJSON is a JSON parser and generator for C++. It was inspired by RapidXml.

* It supports both SAX and DOM style API. The SAX parser is only a
half thousand lines of code.
* It optionally supports SSE2/SSE4.2 for acceleration.
* Header-only implementation. It does not depend on STL.
* Each JSON value occupies exactly 16/20 bytes for most 32/64-bit
machines (excluding text string). By default, it uses a memory
allocator, and the parser allocates memory compactly during
parsing.
* It supports UTF-8, UTF-16, UTF-32 (LE & BE), and their detection,
validation and transcoding internally. For example, you can read a
UTF-8 file and let RapidJSON transcode the JSON strings into UTF-16
in the DOM. It also supports surrogates and "\u0000" (null
character).
05/22