Re: feature request: text property to prevent font-locking

["Stephen J. Turnbull" <stephen@xemacs.org>]

Stefan Monnier writes:
 > >> This might be "relatively simple" to implement, but relative to what,
 > >> I'm not sure.  ;-)
 > > You're well on your way to reinventing "extents", you know. :-(
 > 
 > No, we did that already (except we called them overlays ;-)

Since you apparently need reminding, let me point out that Extents are
capable of providing both text property and overlay behavior, and
several useful combinations of both as well.  "Planes" of text
properties is just one example of behavior that is trivial to
implement with extents.  Drew's desired behavior is trivial to
implement given XEmacs's implementation of text properties (that seems
somewhat accidental to me).

Sure, there are few places where XEmacs implementations vary from
Emacs semantics, but IIRC that's by deliberate choice, with one
exception where XEmacs chose consistency of abstraction over 100%
Emacs compatibility.  99.44% of the time the implementations are not
distinguishable by end users.