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Re: Merged list with regex matches

by Sidhekin (Priest)
on Sep 04, 2007 at 15:49 UTC ( #636966=note: print w/replies, xml ) Need Help??

in reply to Merged list with regex matches

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:

#!/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;

Of course, the regex engine is still run through the alternatives (up until one matches), but at least it looks more elegant. :)

(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.)

print "Just another Perl ${\(trickster and hacker)},"
The Sidhekin proves Sidhe did it!

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