Re: bug in forward-visible-line: Patch

["Stefan Monnier" <monnier+gnu/emacs@rum.cs.yale.edu>]

> ! 		(if (if (eq buffer-invisibility-spec t)
> ! 			prop
> ! 		      (or (memq prop buffer-invisibility-spec)
> ! 			  (assq prop buffer-invisibility-spec)))

BTW, how about a `invisible-p' function that does above ?
Especially since the above is wrong (the assq might match a cons
cell like (foo . nil) which says that it's *not* invisible).

Also while I'm talking about the invisible property.
A lot of code uses t as an invisible value that is assumed to
always be invisible and nil for the opposite.  A recent change
makes buffer-invisibility-spec always contain t so that t should
indeed always be invisible, but I think a better change is to make
the invisibility check something like

	(cond
	 ((eq buffer-invisibility-spec t) val)
	 ((null val) 'visible)
	 ((eq val t) 'invisible)
	 (t (or (memq prop buffer-invisibility-spec)
	        (cdr (assq prop buffer-invisibility-spec)))))

where the change is that nil and t are special values that do
not depend on buffer-invisibility-spec.


	Stefan