character class "alpha"

[Bruno Haible]

Corinna Vinschen wrote:
> there are more of those expressions which are disabled on glibc and
> fail on Cygwin, for instance in test-c32iscntrl.c.  Maybe it's actually
> the better idea to disable them on Cygwin, too, rather than to change
> a working system...

Sure. There is no standard how to map the Unicode properties to POSIX
character classes. Other than the mentioned ISO C constraints for
'digit' and 'xdigit' and a few POSIX constraints, you are free to
map them as you like. For glibc and gnulib, I mapped them in a way
that seemed to make most sense for applications. But different
people might come to different meanings of "make sense".

Bruno