You could always put in a test like 
my $ip_address = "";
if ( $allclasses_file =~ m/_([^_]+$)/ ) {
        $ip_address = $1;
        unless ($ip_address =~ m/\d+\.\d+\.\d+\.\d+/) {
            print "Bad ip value $ip_address\n";
        }
}
return $ip_address;

[download]
or just change your code to use the '\d+\.\d+\.\d+\.\d+' like this 
my $ip_address = "";
if ( $allclasses_file =~ m/_(\d+\.\d+\.\d+\.\d+)$/) {
    $ip_address = $1;
}
return $ip_address;

[download]

In reply to Re: Custom error messages and moose by irirgem
in thread Custom error messages and moose by neilwatson

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