Probably because most of CGI subroutines are autoloaded. If you look into sources of CGI.pm you can find a code that looks like: 

%SUBS = (

...
...
...

'some_sub1' => <<'END_OF_FUNC',
sub some_sub1 {
    ...
    ...
}
END_OF_FUNC

'some_sub2' => <<'END_OF_FUNC',
sub some_sub2 {
    ...
    ...
}
END_OF_FUNC

...
...
...

)

[download]
As you can see defenitions of subroutines are put into a hash as strings. When Perl parses such code it does it very quickly since it doesn't have to parse actual subroutine code.

CGI.pm uses AUTOLOAD to detect undefined subroutine calls and to evaluate subroutines code on fly when they are used.

Update: You can use autoloading techiques yourself for your modules. Probably you don't need to roll your own code for autoloading like CGI.pm does. Use one of these modules: AutoLoader, SelfLoader and autouse.

--
Ilya Martynov (http://martynov.org/)

In reply to Re: Require Load Times by IlyaM
in thread Require Load Times by Anonymous Monk

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