Answer1

In both cases you reuse the same memory space. lexicals only use more memory in case of a recursive subroutine call, but then, you usually want them too.

Anyway, generally you want variables to have the smallest possible scope, so I'd go for option two.

Answer2

I really don't know what you are talking about, and I don't get the example code either.

You cannot "return an array", you always return a list (when the sub is called in list context) or a single scalar value (otherwise). If you want to return a long list efficiently, return an array reference, and never mind copying the reference. If you are worried about the memory that's being consumed by 2 scalars, you should probably be coding in assembly.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Two Questions on "my" by Joost
in thread Two Questions on "my" by C_T

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