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Re: given and for

by moritz (Cardinal)
on Aug 21, 2012 at 09:02 UTC ( #988657=note: print w/replies, xml ) Need Help??

in reply to given and for

First of all for and given are not equivalent, they differ subtly in the scoping of their $_ variable:

use strict; use warnings; use 5.010; $_ = 42; sub f { say } given (23) { f } for (23) { f } __END__ 42 23

So given creates a new lexical $_, while for localizes the existing $_, which results in dynamic scoping.

But the real reason is that code must be readable to humans, and for has the connotation of a loop, whereas given makes it implicit that it's one value that is talked about. So it's all about intent.

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Re^2: given and for
by Monk::Thomas (Pilgrim) on Aug 24, 2012 at 09:20 UTC
    "Switch Statements

    Starting from Perl 5.10.1 (well, 5.10.0, but it didn't work right), you can say [...]"

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