A rule of thumb: use 'use' unless you have a good reason to use 'require'. If you're unsure what to use, use 'use'.

For a short answer, what 'use' does is, it compiles the module (if not compiled already), then runs its code (this is not different from what require does). Afterwards, it calls the import routine (require doesn't do so). And all of it is done at compile time (require does it at runtime).

For a longer answer, and a more detailed explaination of all the differences (I've left out some details) consult the manual pages.

In reply to Re: "Use" vs "Require" by JavaFan
in thread "Use" vs "Require" by perlpal

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