rl_json is a Tcl extension for working with JSON documents. It parses
JSON into a native Tcl_Obj-based representation that preserves the
original value types, and provides a "json" command for extracting,
modifying, constructing, templating, comparing and serialising JSON
values without round-tripping through dicts or lists.

Features include:
 - Fast, strict RFC 8259 parser with string deduplication
 - json get / set / unset / extract / exists / foreach / lmap / template
 - Type-preserving manipulation (strings, numbers, booleans, null)
 - A stub library and C API for use from other extensions
 - Works with Tcl 8.6 and Tcl 9.0
