Re: moving point over invisible and intangible text

[Luc Teirlinck]

Stefan Monnier wrote:

   I'd actually be interested to hear of cases (other than invisible text,
   obviously) where something like `intangible' is necessary, beause I feel
   like the current implementation is problematic.
   The only case I know of is for minibuffer prompts.

[bash2.05b.0 ~ 3 3] grep  -r -l "'intangible" /home/teirllm/emacscvsdir/emacs/
/home/teirllm/emacscvsdir/emacs/lisp/gnus/earcon.el
/home/teirllm/emacscvsdir/emacs/lisp/gnus/gnus-art.el
/home/teirllm/emacscvsdir/emacs/lisp/gnus/gnus-uu.el
/home/teirllm/emacscvsdir/emacs/lisp/buff-menu.el
/home/teirllm/emacscvsdir/emacs/lisp/forms.el
/home/teirllm/emacscvsdir/emacs/lisp/isearch.el
/home/teirllm/emacscvsdir/emacs/lisp/minibuf-eldef.el
/home/teirllm/emacscvsdir/emacs/lisp/ses.el
/home/teirllm/emacscvsdir/emacs/lisp/simple.el
/home/teirllm/emacscvsdir/emacs/lisp/play/gomoku.el
/home/teirllm/emacscvsdir/emacs/lisp/play/landmark.el
/home/teirllm/emacscvsdir/emacs/lisp/progmodes/compile.el
/home/teirllm/emacscvsdir/emacs/lisp/progmodes/vhdl-mode.el
/home/teirllm/emacscvsdir/emacs/lisp/progmodes/vhdl-mode.elc
/home/teirllm/emacscvsdir/emacs/lisp/textmodes/reftex-index.el
/home/teirllm/emacscvsdir/emacs/lisp/textmodes/reftex-toc.el
/home/teirllm/emacscvsdir/emacs/lisp/forms.elc

"/home/teirllm/emacscvsdir/emacs/" contains my entire Emacs CVS tree.

I am not going to paste the (long) output without -l, but I got the
impression from it that most of the files above actually define
intangible regions rather than just checking for it.

There are several files in the list that I am not very familiar with.
I looked at "buff-menu.el" and discovered another bug in the line-move
family of functions related to intangibility.  I also believe that the
use of intangibility in "buff-menu.el" is unnecessary and should be
eliminated.  I will discuss these particular problems separately.

   beause I feel like the current implementation is problematic.

In which sense would you want to change it?  In this case the "use
intangibility only after an interactive command" issue does not seem
to apply, as the Elisp author can always choose which behavior he
wants in this respect by binding `inhibit-point-motion-hooks'.

Sincerely,

Luc.