Using a regex is one way to do it:

use strict;
use warnings;

my $string = 'ABCDEFGHIJKLMNOPQ';
my $tail = 'OPQ';
my $preLen = 4;

if ($string =~ /(.{$preLen})$tail/) {
    print "$1\n";
}

[download]

Prints:

KLMN

[download]
DWIM is Perl's answer to Gödel

In reply to Re: substring problem??? by GrandFather
in thread substring problem??? by Anonymous Monk

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