NAME
    MarpaX::Simple - Generate Marpa-based parser

VERSION
    This document describes version 0.02 of MarpaX::Simple (from Perl
    distribution MarpaX-Simple), released on 2014-05-13.

SYNOPSIS
     use MarpaX::Simple qw(gen_parser);

     my $parser = gen_parser(
         grammar => <<'EOG',
     :start     ::= expr
     expr       ::= num
                  | num '+' num    action => do_add
     num        ~ [\d]+
     :discard   ~ whitespace
     whitespace ~ [\s]+
     EOG
         actions => {
             do_add => sub { shift; $_[0] + $_[2] }
         },
     );

     print $parser->('3 + 4'); # -> 7
     print $parser->('3 + ');  # dies with parse error

    which is a shortcut for roughly this:

     no strict 'refs';
     use Marpa::R2;
     my $grammar = Marpa::R2::Scanless::G->new({source => \$args{grammar}});
     my $pkg = "MarpaX::Simple::gen" . some_random_value();
     my $actions = $args{actions};
     for (keys %$actions) {
         ${"$pkg\::$_"} = $actions->{$_};
     }
     my $parser = sub {
         my $input = shift;
         my $recce = Marpa::R2::Scanless::R->new({
             grammar => $grammar,
             semantics_package => $pkg,
         });
     };

DESCRIPTION
    This module tries to simplify the incantation of producing a parser
    using Marpa::R2 (the scanless interface) by reducing the process to a
    single function call: "gen_parser".

FUNCTIONS
  gen_parser(%args) -> code
    Generate Marpa-based parser.

    Arguments ('*' denotes required arguments):

    *   actions => *hash*

        Supply actions specified in the grammar.

    *   grammar* => *str*

    *   too_many_earley_items => *int*

        Will be passed to recognizer's constructor.

    *   trace_terminals => *bool*

        Will be passed to recognizer's constructor.

    *   trace_values => *bool*

        Will be passed to recognizer's constructor.

    Return value:

TODO
    Allow customizing error message/behavior.

    Support more grammar (Marpa::R2::Scanless::G) options, e.g.:
    "trace_file_handle".

    Support more recognizer (Marpa::R2::Scanless::R) options, e.g.:
    "max_parses", "trace_file_handle".

SEE ALSO
    Marpa::R2

HOMEPAGE
    Please visit the project's homepage at
    <https://metacpan.org/release/MarpaX-Simple>.

SOURCE
    Source repository is at
    <https://github.com/sharyanto/perl-MarpaX-Simple>.

BUGS
    Please report any bugs or feature requests on the bugtracker website
    <https://rt.cpan.org/Public/Dist/Display.html?Name=MarpaX-Simple>

    When submitting a bug or request, please include a test-file or a patch
    to an existing test-file that illustrates the bug or desired feature.

AUTHOR
    Steven Haryanto <stevenharyanto@gmail.com>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2014 by Steven Haryanto.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.