I'm all for customizing your Perl interpreter, either by modules or rearranging the internals. Buuuutt.....

DOCUMENT WHAT YOU DID

If you ever expect someone to understand that uc $foo; actually is calling your uc and not the standard one, you have to write that down. And, make sure you write it down somewhere really prominent. Like, at the beginning of all your scripts. Call your module redefining uc something like "Redefinitions::Unary::uc". Make sure it's obvious what you're doing. And, in that module, make sure you explain exactly how you did it, so I can figure it out.

Or, if you're modifying the interpreter, make sure the shebang line reflects that. Never assume I know more than a really stupid monkey. :)

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/me wants to be the brightest bulb in the chandelier!

Vote paco for President!