Alex Shinn scripsit:

> On the other hand, it just seems surprising enough that w/nocase on one
> case isn't equivalent to the union of all cases.  And that (w/nocase
> upper) != (w/nocase lower).  Enough so that it might be worth making
> an exception for this.

Perhaps then the Right Thing would be to redefine upper and lower to
mean letters which are not only Lu or Ll as the case may be, but are
also part of a casing pair, when in the context of nocase.

On the other hand, PCRE can't do that.

> > and the mathematical letters at U+1D400 et seqq. have case but don't
> > form casing pairs.
>
> ... What were they smoking?

I think it was the correct decision.  There are no mathematical contexts
in which you want to treat italic f and italic F as the same thing; the
distinction is always meaningful.  Consider the formula for the area of
a trapezoid, A = (B + b)h/2, where B and b are the two bases.

--
John Cowan          http://www.ccil.org/~cowan        xxxxxx@ccil.org
Her he asked if O'Hare Doctor tidings sent from far coast and she with
grameful sigh him answered that O'Hare Doctor in heaven was.  Sad was the
man that word to hear that him so heavied in bowels ruthful.  All she
there told him, ruing death for friend so young, algate sore unwilling
God's rightwiseness to withsay.   Joyce, Ulysses, "Oxen of the Sun"