Hello monks,

I would like to know what happens when I declare a variable within a loop such as my $foo within:

foreach my $a(@bar) {
my $foo = &return_something($a);
}

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I frequently use loops with variables scoped within them and was wondering how expensive this was on memory. Am I better off declaring these variables before the block and undefining them on each iteration?
$foo must be a unique instance in memory on each iteration, how long does each instance stay in memory during this loop?
I would also like to know how to undefine a group of variables at once, other than:

($v1, $v2, $vX) = (0, 0, 0);

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Can I undef ($v1, $v2, $vX); or does this only affect the first value in the array? I won't be wanting to refer to these variables outside of these blocks.
Any suggestions?

In reply to Loops and my by ceedee

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