wren-json

Simple JSON parse/stringify for the Wren programming language.

• Parses strict json and relaxed json
  • Comments
  • Unquoted keys
  • Trailing commas
• Stringify emits strict json
• Not 100% complete or to spec as a json parser or stringifier, nor meant to be

API

The API is all static. See test.wren for some basic examples.

Json.parse(string)

Parses a string and returns a Wren Map or List dependening on the contents. It's an error if the string is null. Parsing errors call Fiber.abort (use fiber try).

Json.parse(source_id, source_string)

Parse like above, but with a source identifier for error messages. For example the json file name.

Json.stringify(value)

Returns a string representation of the wren Map or List handed to it. Only handles Wren primitives (Bool, Num, Null, String) and List and Map, no custom types. Uses two space for indentation.

Json.stringify(value, whitespace)

Returns a string representation of the wren Map or List handed to it but with a custom whitespace. e.g if whitespace was " " it would be 4 spaces for indentation, or for example "\t" for a single tab.

Json.stringify(value, whitespace, callback)

Similar to stringify, but does NOT return a value. Instead a callback is called which is handed iterative string results. When writing json to a file or buffer, it can be a LOT more efficient to write directly, rather than allocate a huge amount of strings first and then write that instead. The callback is {|data| write(data) } (see the stringify implementation).

Extra

Running the test file

Grab wren-cli and run it:

wren-cli test.wren

notes

• Several todos, PRs welcome
• There may be bugs, issues etc.
• test.1.json is made up, generated from https://www.mockaroo.com/

This code was written long ago, and was used extensively in luxe for a long while, now ported to this repo as a standalone copy.