I was reading mod_perl2 User's Guide. In a perl startup file section, the phrase "pre-compile common constants" was mentioned. What does that mean?

The startup file also "pre-loads commonly used modules" which I understand, but I don't get what compiling constants means. Thanks for the help!

Here is some relevant code (which I don't understand) from the startup file:

use Apache2::Const -compile => 'OK';
use APR::Const -compile => ':common';

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In reply to Pre-compiling constants in mod_perl by nitin1704

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