Re: modern regexes in emacs

[Perry E. Metzger]

On Fri, 15 Feb 2019 16:18:12 +0200 Eli Zaretskii <address@hidden> wrote:
> > I think the purpose of this thread is to ask for emacs to support
> > PCRE regexpes in commands like `query-replace-regexp`.
> > 
> > Would this even be possible? I can imagine a whole lot of
> > packages breaking if the regexp syntax changed, and changing it
> > just for the user input in interactive functions looks a bit
> > sketchy.  
> 
> It should be possible if we introduce new functions for PCRE, or if
> we mark PCRE regexps in some special way, like put a special text
> property on the string.

I think the right thing is to introduce new functions for new-style
regexps that parallel the old ones, and to allow users to bind things
like the regexp flavors of isearch to the new-style versions if they
wish.

We can decide if we want the new-style versions to be the default
search bindings at some distant date.

One could also very slowly replace use of old-style regexp functions
with the new-style regexp functions in lisp code, but that could be
done over many many years if desired.

Perry
-- 
Perry E. Metzger                address@hidden