pyjson5

A Python implementation of the JSON5 data format.

JSON5 extends the JSON data interchange format to make it slightly more usable as a configuration language:

  • JavaScript-style comments (both single and multi-line) are legal.

  • Object keys may be unquoted if they are legal ECMAScript identifiers

  • Objects and arrays may end with trailing commas.

  • Strings can be single-quoted, and multi-line string literals are allowed.

There are a few other more minor extensions to JSON; see the above page for the full details.

This project implements a reader and writer implementation for Python; where possible, it mirrors the standard Python JSON API package for ease of use.

This is an early release. It has been reasonably well-tested, but it is SLOW. It can be 1000-6000x slower than the C-optimized JSON module, and is 200x slower (or more) than the pure Python JSON module.

Known issues

  • The cls keyword argument that json.load()/json.loads() accepts to specify a custom subclass of JSONDecoder is not and will not be supported, because this implementation uses a completely different approach and doesn't have anything like the JSONDecoder and JSONEncoder classes.