Re: :alnum: broken?

[Paul Eggert]

On 2/28/20 12:09 PM, Eli Zaretskii wrote:
> The regexp specification is not an Emacs-only feature, and I don't
> think we should invent a variant of regexp spec where these particular
> regexps are disallowed.

It would not be an invention of Emacs. It is a variant used in Gnu grep 
(and GNU grep surely does more regexp processing than Emacs does, if we 
look at all the world's computation), and it works fine there. So even 
if we took a strict stance against invention in Emacs regexps (a stance 
that we haven't taken in the past), that stance would not preclude the 
proposed change.

> the particular reason for which you propose this change sounds
> backwards to me.

The goal of this change is to improve the reliability of Elisp code, by 
having Emacs reject invariably-incorrect regexps. It's not "backwards" 
to improve reliability.