L43Peg

A Parse Expression Grammar library for Ruby

Quick Start:
Built In Parsers...
Concepts...
Combinators...
Author
LICENSE

Quick Start: ^

Given we import everyting into our namespace

    require 'l43_peg'
    Kernel.include L43Peg # not the same as RSpec's include

Then we can use the parse function to parse a string or an instance of Input

    parse("a", with: char_parser) => Success
    parse("a", with: char_parser("b")) => Failure

And parsers that do not need any arguments can be passed in as symbols

    parse("a", with: :char_parser) => :ok, "a", _

And we can deconstruct the result into a status, ast and the rest Input instance.

    parse("a", with: char_parser) => :ok, "a", {src: ""}
    parse("ab", with: char_parser) => :ok, "a", {src: "b"}
    parse(Input.new(src: "ab"), with: char_parser) => :ok, "a", {src: "b"}

And we can also deconstruct it into a Hash which provides even more information

    parse("+42", with: int_parser) => {ok: true, ast: 42, parsed: "+42"}

Complete Documentation

Built In Parsers... ^

...are described here

Concepts... ^

...are described here

Combinators... ^

... which are the working horses of any PEG library are described here

Author ^

LICENSE ^

GNU AFFERO GENERAL PUBLIC LICENSE, Version 3, 19 November 2007. Please refer to LICENSE for details.