Regexp::MatchContext 0.0.2

Regexp::MatchContext is Perl module to replace (and improve) $MATCH, $PREMATCH, and $POSTMATCH

SYNOPSIS

use Regexp::MatchContext -vars;

$str = m/(?p) d+ /;

print "Before: $PREMATCHn";
print "Matched: $MATCHn";
print "After: $POSTMATCHn";

$MATCH = 2 * $MATCH; # substitute into original $str

The English.pm module provides named aliases for Perls built-in $`, $& and $ variables: $PREMATCH, $MATCH, and $POSTMATCH. Unfortunately, those aliases suffer the same problems as their originals: they degrade the performance of every single regex in your program, even if youre only using them to get information about a single match.

This module also provides $PREMATCH, $MATCH, and $POSTMATCH, but in a way that only impacts the performance of matches that you specify. That is, these three variables are only set if the most recently matched regex contained the special (non-standard) meta- flag: (?p).

That is:

use Regexp::MatchContext -vars;

$str = foobarbaz;

$str =~ /(?p) foo /x;

# $PREMATCH contains foo
# $MATCH contains bar
# $POSTMATCH contains baz

$str =~ / foo /x;

# $PREMATCH, $MATCH, and $POSTMATCH all undef

The (?p) marker can be placed anywhere within the regex and, except for setting the three context variables on a successful match, is otherwise totally ignored.