pegex - Acmeist PEG Parsing Framework

Pegex is a Acmeist parser framework. It allows you to easily create parsers that will work equivalently in lots of programming languages!

Synopsis

require 'pegex'
result = pegex(grammar).parse(input)

or with options:

require 'pegex'
require 'my_receiver_class'
parser = pegex(grammar, MyReceiverClass)
result = parser.parse(input)

or more explicitly:

require 'pegex/parser'
require 'pegex/grammar'
pegex_grammar = Pegex::Grammar.new do |g|
  g.text = grammar
end
parser = Pegex::Parser.new do |p|
  p.grammar = pegex_grammar
end
result = parser.parse(input)

Description

Pegex is a Acmeist parser framework. It allows you to easily create parsers that will work equivalently in lots of programming languages!

Pegex gets it name by combining Parsing Expression Grammars (PEG), with Regular Expessions (Regex). That’s actually what Pegex does.

PEG is the cool new way to elegantly specify recursive descent grammars. The Perl 6 language is defined in terms of a self modifying PEG language called *Perl 6 Rules*. Regexes are familiar to programmers of most modern programming languages. Pegex defines a simple PEG syntax, where all the terminals are regexes. This means that Pegex can be quite fast and powerful.

Pegex attempts to be the simplest way to define new (or old) Domain Specific Languages (DSLs) that need to be used in several programming languages and environments.

Usage

The pegex.rb module itself is just a trivial way to use the Pegex framework. It is only intended for the simplest of uses.

pegex.rb defines a single function, pegex, which takes a Pegex grammar string as input. You may also pass in a receiver class or object.

parser = pegex(grammar, MyReceiver)

The pegex function returns a Pegex::Parser object, on which you would typically call the parse() method, which (on success) will return a data structure of the parsed data.

See Pegex::API for more details.

Documentation

This Pegex library was ported to Ruby from the Perl module: search.cpan.org/dist/Pegex/

The code and tests were fully ported from Perl to Ruby. Pegex should work exactly the same in both languages. The documentation and examples have not yet been fully ported, but they will be soon enough. For now, refer to the Perl docs.

You can start here: search.cpan.org/dist/Pegex/lib/Pegex.pod

Copyright

Copyright © 2012 Ingy döt Net. See LICENSE for further details.