use Regexp::Assemble. 
use Regexp::Assemble;
my @list = ('12341', '12342', '12343', '13341', '13342');
my $ra = Regexp::Assemble->new;
$ra->add( @list );
print $ra->re

__OUTPUT__
(?-xism:1(?:234[123]|334[12]))

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Boris

In reply to Re: build regexp on a list of patterns by borisz
in thread build regexp on a list of patterns by mod_alex

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