Others have already pointed out the problem with the asterics in your regex. I suspect that you intend to match the middle field if it contains no digits (letters only) or no letters (digits only - the case in all your examples) as well letters followed by digits, but not if the field is empty.

I assume that the asterick after the hyphen is a mistake. You probablly intend to require only one hyphen as a field seperator. Here is an implementation of my assumptions. 

use strict;
use warnings;
use Readonly;
Readonly::Scalar my $PREFIX => qr/DOC_/;
Readonly::Scalar my $FILTER  => qr/
    $PREFIX
    (?: [A-Za-z]+\d* | [A-Za-z]*\d+ )
    -
    [0-9a-z]{3}
    /x;
my @tags = qw( DOC_001_123 DOC_002_214 DOC_001-548 DOC_001-987 );
my @dash_tags = grep {/$FILTER/} @tags;
print "@dash_tags\n";

[download]
Bill

In reply to Re: Regex MATCH by BillKSmith
in thread Regex MATCH by stallion

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