サブ規則の引数リスト

Parse::RecDescent everyday parser 
#!/usr/bin/env perl

use strict;
use Parse::RecDescent;

my $grammar =
q{
    inputs : rule['foo']
    rule   : 'a'          { print "$arg[0]\n"; }
};

my $parse = new Parse::RecDescent ($grammar);

while (<>)
{
    defined $parse->inputs($_) or print "Bad text!\n";
}

で、

a
foo
#!/usr/bin/env perl

use strict;
use Parse::RecDescent;

my $grammar =
q{
    inputs  : keyword rule[$item[1]]
    keyword : 'class'
            | 'def'
    rule    : 'a'          { print "$arg[0]\n"; }
};

my $parse = new Parse::RecDescent ($grammar);

while (<>)
{
    defined $parse->inputs($_) or print "Bad text!\n";
}

で、

class a
class
def a
def