character class "alpha"

[Brian Inglis]

On 2023-07-31 12:43, Bruno Haible via Cygwin wrote:
> 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".

It seems to me that most application developers needing to support 
non-Western-European languages might want a non-POSIX interpretation of digits.

Are the Unicode character attribute classes supported for those application use 
cases that need more than POSIX limitations allow?

I know that I sometimes want to see some alternative numeric digit forms and 
expect to be able to find those with an appropriate grep expression.

-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry