[review] new string type

[Lars T. Kyllingstad]

On Tue, 30 Nov 2010 13:52:20 -0500, Steven Schveighoffer wrote:

> On Tue, 30 Nov 2010 13:34:50 -0500, Jonathan M Davis
> <jmdavisProg at gmx.com> wrote:
> 
> [...]
> 
>> 4. Indexing is no longer O(1), which violates the guarantees of the
>> index operator.
> 
> Indexing is still O(1).
> 
>> 5. Slicing (other than a full slice) is no longer O(1), which violates
>> the
>> guarantees of the slicing operator.
> 
> Slicing is still O(1).
> 
> [...]

It feels extremely weird that the indices refer to code units and not 
code points.  If I write

  auto str = mystring("hæ?");
  writeln(str[1], " ", str[2]);

I expect it to print "æ ?", not "æ æ" like it does now.

On a side note:  It seems to me that the only reason to have char, wchar, 
and dchar as separate types in the language is that arrays of said types 
are UTF-encoded strings.  If a type such as the proposed one were to 
become the default string type in D, it might as well wrap an array of 
ubyte/ushort/uint, since direct user manipulation of the underlying array 
will generally only happen in the rare cases when one wants to deal 
directly with code units.

-Lars