I got an unexpected behavior in the value of a global variable used as an iterator in a "for" loop: It's current value is not accesible from a subroutine called on each iteration.

#!perl

use strict;
use warnings;

my $i = 0;

for $i (1 .. 3) {
  show();
}

sub show {
  print "$i\n";
}

[download]

I was expecting 1 2 3, but got 0 0 0 !!!

If I add a "my" in the "for" loop, I am saying that the new $i variable has it's own scope, and I understand that the sub cannot see it, but without a "my" in the "for", shouldn't the scope of $i be the same everywhere?

If I don't declare and initialize the $i variable, I get an error unless I also add a "my" in the "for" loop. That says it is the same variable. Why to add an extra scope to it during runtime?

A workaround is to declare another iterator variable in the "for" and assign it to $i as the first step in the loop...

In reply to Access a global variable from a subroutine when used as "for" iterator by vitoco

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