On Thursday, August 02, 2012 00:29:09 Walter Bright wrote: > > If we want to be able to operate on ranges of UTF-8 or UTF-16, we need to > > add a concept of variably-length encoded ranges so that it's possible to > > treat them as both their encoding and whatever they represent (e.g. code > > point or grapheme in the case of ranges of code units). > > No, this is not necessary.
It is for ranges in general. In the general case, a range of UTF-8 or UTF-16 makes no sense whatsoever. Having range-based functions which understand the encodings and optimize accordingly can be very beneficial (which happens with strings but can't happen with general ranges without the concept of a variably-length encoded range like we have with forward range or random access range), but to actually have a range of UTF-8 or UTF-16 just wouldn't work. Range-based functions operate on elements, and doing stuff like filter or map or reduce on code units doesn't make any sense at all. - Jonathan M Davis
