dear perl monks,

as I try to improve the performance of my little skript and even google can't answer my question, I come here to ask for a bit of your wisdom, since you were always able to help me in the past :)

in my skript I have some regular expressions, which get executed several million times within few minutes. currently they get compiled every time, with this compiling eating several percent of total execution time, so it would be great to precompile them to avoid that compile each and every time.

example:

$string1 =~ s/$string2//g;

where $string1 changes often, but $string2 is used a few million times. after I read some texts in the net, I would replace it by

$string2 = qr/$string2/g;
$string1 =~ s/$string2//;

[download]

Problem: this does not compile because of the /g option.

after rewriting it to

$string2 = qr/$string2/;
$string1 =~ s/$string2//g;

[download]

it now does compile, but the profiler shows me, that the precompile doesn't work and the regexp still gets compiled each and everytime :(
is there anything I can do to avoid that compilation and speed up my skript?

thanks ahead!

In reply to precompiling regular expressions by Anonymous Monk

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