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Pegex

NAME

Pegex − Pegex Parser Generator

SYNOPSIS

    use Pegex;
    my $data = pegex($grammar)−>parse($input);

or more explicitly:

    use Pegex::Grammar;
    use Pegex::AST;
    my $grammar = Pegex::Grammar−>new(
        grammar => $grammar,
        receiver => Pegex::AST−>new(),
    );
    $grammar−>parse($input, 'rule_name');
    my $data = $grammar−>receiver−>data;

or customized explicitly:

    package MyGrammar;
    use Pegex::Grammar −base;
    has grammar_text => "some grammar text goes here";
    package MyReceiver;
    use Pegex::Receiver −base;
    got_some_rule { ... }
    got_other_rule { ... }
    package main;
    use MyReceiver;
    use MyGrammar;
    my $receiver = MyReceiver−>new();
    my $grammar = MyGrammar−>new(
        receiver => $receiver,
    );
    $grammar−>parse($input);
    my $data = $receiver−>data;

DESCRIPTION

Pegex is a Acmeist parser framework. It is a PEG parser grammar syntax, combined with PCRE compatible regular expressions as the match tokens. Pegex draws heavily from Perl 6 rules, but works equivalently in many modern programming languages.

With Pegex you can easily define new mini languages that can be easily compiled in many programming languages.

A REAL WORLD EXAMPLE

TestML is a new Acmeist unit test language. It is perfect for software that needs to run equivalently in more than one language.

TestML has a language specification grammar: http://www.testml.org/specification/language/

The Perl6 implementation of TestML uses this grammar in: http://github.com/ingydotnet/testml−pm6/blob/master/lib/TestML/Parser/Grammar.pm

All other implementations of TestML use this Pegex grammar: http://github.com/ingydotnet/testml−pgx/blob/master/testml.pgx

In Perl 5, Pegex::Compiler is used to compile the grammar into this simple data structure (shown in YAML ): http://github.com/ingydotnet/testml−pgx/blob/master/grammar.yaml

The grammar can also be precompiled to JSON: http://github.com/ingydotnet/testml−pgx/blob/master/grammar.json

Pegex::Compiler further compiles this into a Perl 5 only graamar tree, which becomes this module: http://github.com/ingydotnet/testml−pm/blob/master/lib/TestML/Parser/Grammar.pm

TestML::Parser::Grammar is a subclass of Pegex::Grammar. It can be used to parse TestML files. TestML::Parser calls the "parse()" method of the grammar with a TestML::Receiver object that receives callbacks when various rules match, and uses the information to build a TestML::Document object. http://github.com/ingydotnet/testml−pm/blob/master/lib/TestML/Parser.pm

REPOSITORY AND COMMUNITY

The Pegex module can be found on CPAN and on GitHub: http://github.com/ingydotnet/pegex−pm <http://github.com/ingydotnet/pegex-pm>.

Please join the Pegex discussion on #pegex on irc.freenode.net.

AUTHOR

Ingy doet Net <ingy AT cpan DOT org>

COPYRIGHT

Copyright (c) 2010. Ingy doet Net.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See http://www.perl.com/perl/misc/Artistic.html

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