note Sidhekin <p> On the assumption that every $cn will match at most one $bn (or that you don't care about more than the first), you could precompile a regex and use the result of the match: </p> <code> #!/usr/bin/perl use strict; use warnings; my @CS_CHECKS = ( '00012345', 'D123470', '0000123450', '0000023456', '50000123990' ); my @B_CHECKS = ( '1234', '12345', '123990', '12399' ); my $re = do { my $x = join '|', map "\Q$_", @B_CHECKS; qr/^[056]0+($x)$/ }; $_ =~ $re and print "$1 = $_\n" for @CS_CHECKS; </code> <p> Of course, the regex engine is still run through the alternatives (up until one matches), but at least it <em>looks</em> more elegant. :) </p> <p> (Oh, and it may be faster too, what with not having to recompile the regex again and again. But don't quote me on that.) </p> <div class="pmsig"><div class="pmsig-106949"> <p align=center> <font size=-1><code>print "Just another Perl ${\(trickster and hacker)},"</code></font> <br>The Sidhekin <b>proves</b> Sidhe did it!</p> </div></div> 636961 636961