If you would have just used qr, you wouldn't have had this problem. Plus, Perl would have checked for you if $pattern actually contains a valid regex on its own, and not just test on the larger pattern. 
my $pattern = qr/AB/;

[download]
or 
my $pattern = "AB";
$pattern = qr/$pattern/;

[download]
It also incorporates regex switches into the regex, so you can't globally override them. For example, if $pattern looks like "A B", if you use it in /$pattern/x, the space would be stripped from the subpattern. But not with qr.

In reply to Re: Regex help by bart
in thread Regex help by gri6507

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