# make_parser.pl

use strict;
use warnings;

use Parse::RecDescent qw( );

my $grammar = <<'__EOI__';

    {
        use strict;
        use warnings;

        sub dequote {
            my ($s) = @_;
            $s =~ s/^"//;
            $s =~ s/"\z//;
            $s =~ s/\\(.)/$1/sg;
            return $s;
        }
    }

    parse     : list /\Z/ { $item[1] }

    list      : term list_[ $item[1] ]

    list_     : "AND" <commit> and_list
                { [ $item[1] => $arg[0], @{$item[3]} ] }

              | "OR"  <commit> or_list
                { [ $item[1] => $arg[0], @{$item[3]} ] }

              | { $arg[0] }

    and_list  : term and_list_
                { [ $item[1], @{$item[2]} ] }

    and_list_ : "AND" <commit> term and_list_
                { [ $item[3], @{$item[4]} ] }

              | { [] }

    or_list   : term or_list_
                { [ $item[1], @{$item[2]} ] }

    or_list_  : "OR" <commit> term or_list_
                { [ $item[3], @{$item[4]} ] }

              | { [] }

    term      : IDENT
              | STRING
              | '(' list ')' { $item[2] }

    IDENT     : /\w+/
    STRING    : /"(?:\\.|[^\\])*"/s { dequote($item[1]) }

__EOI__

Parse::RecDescent->Precompile($grammar, 'Parser')
    or die("Bad grammar\n");