I have a bunch of regular expressions in a text file that is frequently read, but infrequently changed. I want to compile all of the regexes, and store them in another file. I tried doing this like so: 
$re = qr/$foo/;
print FILE $re, "\n";
# ... and at a later time ...
$re = <FILE>
chomp $re;
if($line =~ /$re/) { # blah blah blah....

[download]
and this appears to work. My only question is this: Am I truely saving CPU time by doing this, or does perl still have to do something special to turn that string I got from a file into a regular expression.

In reply to precompiling regexes by bless$self=>perlmonks;

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