Re: org-mode and mode hooks.

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Stefan Monnier wrote:

   > ! @strong{Warning:} Only use a non-@code{nil} @var{mode} argument when
   > ! you use @code{font-lock-add-keywords} or
   > ! @code{font-lock-remove-keywords} in your @file{.emacs} file.  When you
   > ! use these functions from a Lisp program (such as a minor mode), we
   > ! recommend that you use @code{nil} for @var{mode} (and place the call
   > ! on a hook) to avoid subtle problems due to the details of the
   > ! implementation.

   The intention with the above text was to make a non-nil argument
   semi-obsolete,

That may be what the above text _intends_ to say, but it definitely is
not what it says.  It even says to always use a non-nil argument when
used from .emacs, probably the most important use.  The text is very
vague, for instance, it says to add them to "a hook" whereas there are
only two hooks for which it will work properly (for compliant major
modes), the major mode hook and after-change-major-mode-hook (if you
want to get a "permanent local" type behavior).

The misleading text in question made me loose a lot of time.  Getting
rid of it will prevent other people from loosing a lot of time.

In my replacement text, I document the actual situation: a non-nil
argument does not apply to derived modes, a nil one must be added to a
major mode hook and if used this way, it will apply to derived modes
_if_ the major modes in question follow the conventions.

Sincerely,

Luc.