I typically use: 
my $NAME = "abc";
...
if ($input =~ /$NAME/) {
    ...
}

[download]
It does use a variable, but it saves a sub. The advantage of being able to interpolate variables to me outweight the advantages 'constants' give me.

In reply to Re: using constants in regex/search by JavaFan
in thread using constants in regex/search by geniezlife

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