Re: new text property

[Colin Walters <walters@gnu.org>]

On Mon, 2002-06-10 at 02:38, Stephen J. Turnbull wrote:

> What I do know is that font-lock itself has a minimum of five
> implementations (font-lock, font-lock-cache, lazy-lock, lazy-shot, and
> jit-lock). 

Those are all ways of dynamically searching for text and placing `face'
properties on them.  That's a very different approach from the way
`font-lock-face' is used.

Really, `font-lock-face' has nothing to do with what people
traditionally think of as "Font Lock" (i.e. regexps, searching), except
that it happens to be toggled on and off when the user types M-x
font-lock-mode.  The amount of code dealing with `font-lock-face' in
font-core.el amounts to about 8 lines.

> Primitive highlighting has at least three interfaces
> (overlays, text properties, extents).  This looks like an area ripe
> for consolidation, not proliferation, of APIs to me.

Yes, but adding `char-property-alias-alist' will not really increase the
difference between interfaces.  XEmacs appears to already have
`default-text-properties', which is similar.

> I also don't like the idea that semantics apparently depend on whether
> a reference is an "original" or an "alias".

They don't.

> Thus the warning.  This may be the right thing to do, but I want to
> make sure that XEmacs people _discuss_ this change rather than simply
> adopt it for the sake of compatibility.

I understand that.  But could you please study `font-lock-face' a little
bit more carefully?  The points you have raised so far don't really
apply to it.