in reply to regex and substrings

If you just need a check, and it doesn't have to be a regex, then maybe index() and ne would work?

if( index($str1, $str2) > -1 && $str1 ne $str2 ){ print "$str2 is a substring of $str1\n"; }

With tests to make sure it works as expected:

#!/usr/bin/env perl use strict; use warnings; use Test::Simple; my $str1 = "helloworld"; my $str2 = "hello"; my $str3 = "hello"; ok( is_substring($str2, $str1), "str2 is a substring of str1"); ok( !is_substring($str3, $str2), "str3 is not a substring of str2"); sub is_substring { my ($substring, $string) = @_; return 1 if index($string, $substring) > -1 && $string ne $substri +ng; }