On Sun, May 11, 2014 at 7:56 AM, John Cowan <xxxxxx@mercury.ccil.org> wrote:

Alex Shinn scripsit:

> What I will do is specifically note that
>
> (w/nocase upper)
> (w/nocase lower)
> cased
>
> are all the same thing (where cased is characters with
> the cased (L&) property),

But they aren't the same thing; I already showed that.

Yes. I'm proposing _defining_ them to be the same thing.

Specifically, in the w/nocase text after the explanation of

how char-sets are handled, I would include:

As a special case, the pre-defined named character sets

upper and lower (and their aliases upper-case and lower-case)

are defined to match all characters with the cased property (L&).

Note also all other pre-defined named character sets are

equivalent to themselves under w/nocase.

Rationale: The differences between the case insensitive

lower and upper and the cased property are few and unlikely

to match user intention. Moreover, unlike the algorithmically

mapped upper and lower char-sets, the cased property is

readily available in most Unicode implementations.

And the only realistic alternative I can see is making this

special case optional, so that either behavior is correct.

Alex