Re: modern regexes in emacs

[Eli Zaretskii]

> From: Clément Pit-Claudel <address@hidden>
> Date: Fri, 15 Feb 2019 13:46:23 -0500
> 
> On 15/02/2019 13.36, Eli Zaretskii wrote:
> > I proposed to have a separate set of functions that will accept PCRE
> > syntax.  That would allow everyone to have what they want: you to use
> > the "classic" regexps, and those who want PCRE to have that.  Where's
> > the problem with that?
> 
> I think that solution doesn't let you pass regexps using fancy PCRE features 
> to existing code through defvars and defcustoms.  As a concrete example, 
> sometimes assertions would be useful in regexps that define outlines, or in 
> syntax highlighting, or in comment marker definitions. 

Then those who want that will need to come up with either a function
that converts PCRE to the traditional syntax, or invent new functions
for outlines, syntax highlighting, etc. for that.  You cannot
seriously propose a global setting that will switch to PCRE syntax, as
that will cause a lot of breakage.

The original motivation was to provide PCRE in _commands_.  Suddenly
we are talking about using PCRE everywhere?  Please hold your horses.