Re: UTF-8 Functions

[Darin Adler <darin bentspoon com>]

On Monday, July 2, 2001, at 04:18  PM, Owen Taylor wrote:

> The question, I guess is whether it is worth adding:
>
> g_ut8_collate_key_casefold (), which is currently
>
>  g_utf8_collate_key (g_utf8_casefold (string));
>
> But might eventually be implemented as:
>
>  g_utf8_collate_key_extended (string,
>                               G_COLLATE_SECONDARY,
>                               G_NORMALIZE_ALL_COMPOSE);
>
> [ There are issues of correctness here as well as efficiency ]
>
> It's certainly easy enough to do ... just a few lines of code.  My
> main hesitation is whether we know yet whether that is the right part
> of the parameter space to give a special name.

Clear analysis as usual.

I think perhaps I want to retract my previous comment/request. If I 
understand correctly, g_utf8_collate_key (without g_utf8_casefold) will 
still typically sort strings in a way that is not unduly sensitive to case.
 In other words, we get this kind of order:

    A, a, B, b

not this kind:

    A, B, a, b

If that's so, then I think it's not particularly important to add the case 
folding version. It's only needed when you want to "partly collate" things 
and put a bunch of identical items into the same bucket. That's not the 
usual case, I don't think.

It might be common to case fold and normalize and then use the resulting 
string as a key. But I can't think of a case where you'd want to case fold 
and normalize and then still want to collate in a locale-specific way.

    -- Darin