standard ranges

[Roman D. Boiko]

My point (and the reason I somehow hijacked this thread) is that 
such functionality would be useful for random access over narrow 
strings. Currently random access is missing.

Also this approach fits nicely if random access is needed to 
Unicode characters, not just code points.

I don't see much practical value in proposals to reconsider 
current string implementation. Arguments have been presented that 
it improves consistency, but as Andrei replied, consistency 
itself has many dimensions. Proposed changes have not been 
described in detail, but from what I understood, they would make 
common use cases more verbose.

In contrast, I do see value in Select / Rank indexing. Does 
anybody agree?