Re: Should invisible imply intangible?

[Stefan Monnier]

>     > Is there any practical use for text which is invisible but not
>     > intangible?
> 
>     Yes.  Check out lisp/reveal.el (aka reveal-mode) 
> 
> Ok, I am convinced.  But what do you think of the view that invisible
> should imply intangible unless something like reveal.el is used?
> We could have a flag which says whether invisible implies intangible.
> It could default to t, and reveal-mode could set it to nil.

But reveal.el does not apply to all invisible text in a buffer.
Only to the text that's made invisible by an overlay and only if
the invisibility spec says that it should be replaced by an ellipsis.

Also, as David Kastrup has mentioned repeatedly, intangible text tends
to break lots of things, so we probably want to use something else.
For example: automatically move point to a visible area after each command
(and after post-command-hook, of course) or during redisplay (I believe
there is already such a feature for text with a `display' property).

The current intangibility which moves point to a tangible area for
each and every point motion tends to be too intrusive.

I think that a "move to visible, after post-command-hook" or something
like that might be appropriate.  And it wouldn't conflict with reveal.el
(although it could still conflict if reveal.el was changed to use an idle
timer rather than post-command-hook).


        Stefan