access foreach index counter for Iterate n times

[mw]

On Saturday, 21 May 2022 at 16:11:50 UTC, Adam D Ruppe wrote:
> On Saturday, 21 May 2022 at 15:43:59 UTC, mw wrote:
>> Same question:
>> Why 3 bytes? Not 4 bytes?
>
> Same answer: it is pointing at the character in the ORIGINAL 
> ARRAY. The original array is NOT made out of dchars but it 
> reads and converts on the fly while maintaining the correct 
> position.

UTF variable-length encoding is the answer I'm looking for.

> See that's the beauty of it: how it gets there can be pretty 
> complicated (especially when going backwards with 
> foreach_reverse), but it always gives the right answer.

OK, it's a loop array index, not a "loop counter"; so most of 
time these two things are the same, but in this special case of 
UTF variable-length encoding they are different.

two comments:

1) can we also have a true "loop counter"? coming from a numeric 
computation application background, "loop counter" certainly is 
very useful.

2) can we also make it work for range? i.e. the question in my 
original 1st post.