On 3/15/07, MichaelL_at_frogware.com <MichaelL_at_frogware.com> wrote:
> > If string-ref also required O(1) time complexity, then you'd be right.
> > But it doesn't; it's perfectly fine to implement string-ref on top of
> > underlying UTF-8 or UTF-16 character sequences; you just have to settle
> > for O(N) performance.
>
> Are you suggesting that indexes represent code points rather than code
> units? I haven't seen anyone do that, not as the one-and-only interface to
> elements of a string. Have you? And do you think UTF-8/UTF-16
> implementations should be *required* to do that? (Obviously, then,
> string-length would have to return the number of code points rather than
> the number of code units.)
>
SBCL does that.
http://sbcl.sourceforge.net/sbcl-internals/Character-and-String-Types.html
Wasn't the 16-bit java internal representation chosen before unicode
exhausted the 0-0xffff range? (i.e. it was an unfortunate design
decision)
Alexander
Received on Thu Mar 15 2007 - 13:31:31 UTC