in reply to Simple question about foreach and my.

As others have put it, it's a matter of scoping, both are correct for 99.9% of the cases out there. But, as an example of where you'd want to have the my statement elsewhere of the foreach statement: 
my $element;
foreach $element (@set_of_numbers)
{
    last if $element < $critical_value;
}
print "$element is below the critical value.\n";

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If the my was inside the foreach, $element would not have scope outside the loop, and therefore you'd run into problems with the print statement.
Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

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Re: Re: Simple question about foreach and my.
by petral (Curate) on Mar 27, 2001 at 23:39 UTC
    Actually, I don't think that works. The reasoning is that since $_ is local'ed inside foreach loops, any loop variable should be. This is supposedly in support of the principle of "least surprises". Anyway, with 5.05003 I get: 
    > perl -lwe '$x=$y=0; foreach $x (0..9) { ++$y } print "$x, $y"'
0, 10
> perl -lwe 'my($x,$y)=(0,0); foreach $x (0..9) { ++$y } print "$x, $y
+"'
0, 10
> perl -lwe '$y=0; foreach $x (0..9) { ++$y } print ! defined $x,", $y
+"'
1, 10
> perl -lwe 'my $y=0; foreach my $x (0..9) { ++$y } print ! defined $x
+,", $y"'
Name "main::x" used only once: possible typo at -e line 1.
1, 10
>

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