Re: Rational Ranges - Rafal and Mike's opinion? (Bug 23393).

[Carlos O'Donell <carlos@redhat.com>]

On 07/24/2018 04:45 PM, Rafal Luzynski wrote:
> 23.07.2018 20:09 Carlos O'Donell <carlos@redhat.com> wrote:
>> [...]
>> Rafal,
>>
>> As localedata maintainer what is your opinion of changing the meaning
>> of [a-z], [A-Z], and [0-9] to be rational ranges for *all* locales
>> which mean exactly the latin character sequences you would expect
>> e.g. {a,b,c,d,e,f,g,h,i,j,k,l,n,m,o,p,q,r,s,t,u,v,w,x,y,z} for [a-z],
>> [A-Z] likewise, and {0,1,2,3,4,5,6,7,8,9}?
> 
> Having discussed this off-list my answer is: I'm in favor of implementing
> rational ranges treating [a-z], [A-Z], [0-9], and all their subsets as
> code-point ranges.  But I understand that this is possible only in 2.29.
> Therefore for 2.28 I support this data-based solution.

From the perspective of the user of the library and the locales the
rational ranges we implement will look as-if they were code point ranges
for the ranges in question e.g. a-z, A-Z, 0-9 and their subranges.

For 2.28 we will implement rational ranges for [a-z], [A-Z], and [0-9],
and all of their subsets via a data-only solution. Just wanted to make
it clear that all subsets will be treated as rational ranges.

It is only for other subsets like [!-~] (ASCII range) where we will not
have a rational range until we switch to making ranges operate on code
points. That will be a 2.29 optimization.

OK, I will prepare a patch to fix this.

Cheers,
Carlos.