Make the \d optional, not the capture:

use strict;
use warnings;

my $str;
#$str = "6%var% after";
$str = "%var% after";  # <-- warning is triggered

$str =~ s/(\d?)%var%(.*)/$1REPLACED$2/;  # <-- moved the '?'

print "$str\n"

[download]

By the way, I don't get the warning under Active Perl 5.6.1, but I did with perl v5.8.0 built for i386-freebsd

In reply to Re: Regex triggering uninitialised values by ikegami
in thread Regex triggering uninitialised values by kiat

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