You may want to look into the regex quotation operator, qr. The $" variable can be used to force alternation into a quoted array. 

#!/usr/bin/perl
use warnings;
use strict;

chomp(my @list = <DATA>);

my $regex = do {
    local $" = '|';
    qr/@list/;
};

print $regex, $/;

my $s = 'huey';
print "match:\t$s\n" if $s =~ $regex;

__DATA__
huey
dewey
louie

[download]
I've demonstrated some tricks which reduce the visual noise. chomp can be applied to a list, the diamond op returns all lines in array context, and the elements of a quoted array are seperated by $".

After Compline,
Zaxo

In reply to Re: creating a regular expression's alternation dynamically? by Zaxo
in thread creating a regular expression's alternation dynamically? by Anonymous Monk

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