std.string.reverse() for mutable array of chars

[bearophile]

Jonathan M Davis:

> And as I explained in bug# 7085, reverse's behavior with regards to dchar[] is 
> completely correct. It's reversing the code points, _not_ the graphemes.

OK. Maybe I will open a differently worded enhancement request, for a grapheme-aware std.string.


> If you want to reverse a char[], then cast it to ubyte[] and reverse that. If 
> you want to reverse a wchar[], then cast it to ushort[] and reverse that. In 
> Phobos, strings are ranges of dchar, so reverse is going to reverse code 
> points. If you want it to reverse code units instead, then you just use the 
> appropriate cast. There's no reason to have it reverse the code units and 
> completely mess up unicode strings.

I am not interested in reversing code units. Sorry if my post has led to this wrong idea. For this specific problem I am not going to cast to ubyte[] or ushort[] because it gives very wrong results.

It's possible to write a "correct" (that doesn't take into account graphemes) reverse even if you do not use casts, keeping the array as char[] or wchar[], reversing the bytes, and then reversing the bytes of each variable-length codepoint. This is what I was asking to an in-place reverse().

Bye,
bearophile