Re: RFC 120 (v2) Implicit counter in for statements, possibly $#.

"Christopher J. Madsen" <[email protected]> writes:

> Jonathan Scott Duff writes:
>  > Excellent summary of why an explicit index is a Good Thing as compared
>  > to the programmer doing it himself.  I think the syntax would need to
>  > be different though, how do you use implicit $_ and an index?  (Don't
>  > Do That is not an answer because people will want it)  Here are some
>  > ideas:
>  > 
>  > 	# Gosh, let's overuse : like python! ;-)
>  > 	for $item:$index (@array) { ... }
>  > 	for :$index (@array) { ... }		# $_ and counter
>  > 
>  > 	for (@array : index($index)) { ... }
>  > 	
>  > 	for (@array) $index { ... }
> 
> I would say you can't use implicit $_ with an index; you use explicit
> $_ instead.
> 
>     foreach $_ $index (@array) { ... }

Others have commented on how easy is it to get this wrong.  May I
propose an alternate syntax?  Instead of trying to hack C<for> loops
to do what you want, extend C<each> to iterate over arrays in-order.
Then the examples become:

    while (($index,$item) = each @array) { ... }

Actually, this suggests that C<values @array> should return
C<(@array)> (a copy of the values), and C<keys @array> the list
C<(0..$#array)>.  But those aren't very useful.

[...]

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