Ah! Very wonderful of you to point out the mod_perl gotcha! Indeed, require would be a catastrophe under this environment? The calls would be unavailable or the whole thing would have to be recompiled, etc?

Yes, as you speak. The modules are loaded on call, not by default. And that is why it runs fast, because what's not "used" is not sought.

This is not just useful in cgi by any stretch of the imagination.
This is also *incredibly* useful in command line apps that may be able to do various different things.
Or maybe your script has a %50 chance of failure for some reason, and should exit as soon as possible.
For example, things on cron, that maybe have to do an expensive task at any moment, and are checking every 60 seconds if this procedure should or not happen.
The require would not be reached unless conditions are met, thus, quick and cheap.

Really helps speed things up, with an interpreted language.

In reply to Re^2: Do multiple use statements across module dependency hierarchies require as little expense as multiple require statements? by leocharre
in thread Do multiple use statements across module dependency hierarchies require as little expense as multiple require statements? by leocharre

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