Looping over an array does not actually change it's contents (as far as I know, maybe there are some special arrays).
use Data::Dumper;
@arr = (1,2,3);
print Dumper(\@arr);
foreach $i (@arr) {
  # not doing or changing anything here.
}
print Dumper(\@arr);

[download]
Shows that the array contents have not been changed. The same should hold for while loops.

Update: I guess I will mention that in PHP there are loop counters that you sometimes have to reset each time you want to iterate over an array. I don't know of anything like that in Perl though. Maybe that's where this question came from.

In reply to Re: how do foreach and while affect an array? by superfrink
in thread how do foreach and while affect an array? by Anonymous Monk

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