When matching terminals, Parse::RecDescent seems to produce a match if a token begins with the terminal, rather than trying for an exact match. This code demonstrates this:

#!/usr/bin/perl

use warnings;
use strict;

use Parse::RecDescent;

my $grammar = q{
    FOO: "foo"
};

my $p = Parse::RecDescent->new($grammar);

my @tests = ("foo", "foo ", "foo bar", "football", "fog", "barfoo", "b
+ar foo");

for my $test (@tests) {
    if (my $ret = $p->FOO($test)) {
        print "match: '$test' -> '$ret'\n";
    }
    else {
        print "no match: '$test'\n";
    }
}

[download]

This isn't what I want. I want it to produce an error/return undef when what was entered doesn't match in full, rather than simply eating the remainder.

I doubt this is a bug, because it seems too trivial, so I suspect that this is actually a lack of understanding of parsing in general on my part. Could someone please set me straight here? Thanks!

In reply to Matching terminals with Parse::RecDescent by fce2

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