On Oct 24, 2013, at 7:19 AM, matz (Yukihiro Matsumoto) wrote:

>  * Should non number indexing be allowed? (e.g. n:m that would cause =
conflict)

I think that variables should be usable as components of the range (e.g. =
n:m).  See my other message about avoiding conflicts with {n:m}.

I also can't think of any reason to prohibit non-number first and last =
components (just like Range currently supports), but I think step size =
(if adopted as part of this proposal) would have to be numeric.

Dave