Subject: bug#36167: [PATCH] Replace manually crafted hex regexes with [[:xdigit:]]

From: Andy Moreton <[email-masked]>
Date: Tue, 11 Jun 2019 20:56:09 +0100

On Tue 11 Jun 2019, Eli Zaretskii wrote:

>> Date: Tue, 11 Jun 2019 10:19:17 -0700 (PDT)
>> From: Drew Adams <[email-masked]>
>> Cc: [email-masked], [email-masked], [email-masked],
>>         [email-masked]
>> 
>> > Isn't it clear already?
>> 
>> I meant [:xdigit:], not [:digit:], in my reply.  Sorry for
>> the typo.
>
> :xdigit: is also clearly documented:
>
>   ‘[:xdigit:]’
>        This matches the hexadecimal digits: ‘0’ through ‘9’, ‘a’ through
>        ‘f’ and ‘A’ through ‘F’.

The docs for [:digit:] and [:xdigit:] seem clear enough, but there is
one other minor point that could be clarified.

The [:alnum:] and [:alpha:] are based on (unspecified values of) the Unicode
general-category property, but [:digit:] is not. Thus [:alnum:] includes
other numeric characters that are not matched by [:digit:].

    AndyM