I like to put an explicit name in instead of $_, like so:

for my $value (@array) {
  do_something_with($value);
}
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Going back to the C/C++ style comparison, I also think $value is more readable than $array[$i], but that's a matter of opinion and/or of naming things well.

But remember that $value is not available outside the for loop. If you're worried about knowing where you are in the array, I've found I don't need to worry most of the time or I can just create put 'my $i = 0;' before the loop and do $i++ each time round.