I need to find two consecutive occurrences of a given character. The following SSCCE works ('cc' matches, 'cz' does not match), but I have to turn off 'uninitialized' warnings prior to the regex to make it work without getting 'uninitialized' warning messages about $1. Do you know a better way to do this, preferrably without the need to suppress warnings?

On a side note, the "start of string" anchor (^) in the regex is fine, but if I add an "end of string" anchor to the regex (either '$' or '\z') the match fails. The match should not fail with the addition of an "end of string" anchor, because each string is exactly 2 characters long.

Where is Jeffrey Friedl when you need him? (ha ha) :-) 

#!/usr/bin/perl
use strict;
use warnings;

my @txt = ('cc','cz');
for (@txt) {
    no warnings 'uninitialized';
    if (m/^(.)$1/) {
        print "True   \$_ = |$_|   \$1 = |$1|\n";
    } else {
        print "False  \$_ = |$_|   \$1 = |$1|\n";
    }
    use warnings;
}

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"It's not how hard you work, it's how much you get done."

In reply to How To Remove Warnings From Regex by roho

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