RE: describe-mode "some-mode"?

[Drew Adams <drew.adams@oracle.com>]

> > `help-documentation' is defined in `help-fns+.el'
> > (http://www.emacswiki.org/emacs-en/download/help-fns%2b.el).
> > It is like the vanilla function `documentation', but
> > it uses `help-substitute-command-keys' so that keys
> > mentioned in the help become links to their doc.
> 
> Why isn't such a helpful feature itself vanilla?

There are lots of helpful features that are not in vanilla Emacs.
The choice is up to the Emacs maintainers.

(And one person's helpful feature is can be another's PITA.)

> > Using only vanilla functions:...
> 
> And make one of those vanilla as well!
> And then - as it seems only the lowercase m is employed
> by the help system, for describing the current buffer
> modes: (global-set-key "\C-hM" 'my-describe-mode)
> 
> But, for message-mode, those don't give identical
> output for me with respect to the minor modes.

No, they don't - see my first message.
(It has nothing to do with `message-mode'.)
The first one does not try to include minor-mode info.
That's easily added if you want it.

The point was to show that all of this is already available,
even if not in the form of a ready-made command.  The function
`documentation' that you were looking for, is used here, for
instance.

As is typically the case, the elements of what is needed to
cobble together such a "feature" (command) are in the Emacs
code.  E.g., just look at the definition of `describe-mode'.

It often happens that a given user wants a simple command to
do XYZ, while other users don't feel such a need.  And even
the same user might feel like s?he wants an XYZ command/feature
now, especially when new to Emacs (witness the many "How do I
do this `vi' thing in Emacs?"), and s?he might find later that
s?he really does not really need/want it.

How someone interacts with Emacs changes, with time and with
changes to the code s?he uses.  Many users end up making heavy
use of this or that 3rd-party library, which changes how they use
Emacs, sometimes radically.  And core Emacs features change over
time too - usually for the better.

Some features that were practically unusable in the past (or were
at least not used much) have become things that people use all of
the time.  And sometimes all it took was a few tweaks to the UI
to make them more convenient or more powerful.

That is really the power of Emacs: that every Joe & Jane ends up
fiddling with things to slightly improve them.  This often happens
because someone has an itch to scratch.  But Emacs itself deserves
a lot of the credit, because it is an environment conducive to
customization, er, improvement.

> Perhaps Gnus enables something in a hook that is not part of
> plain message-mode. So you should be careful separating
> when you want to describe a mode in general, and the
> mode specifically in effect for the current buffer!

No, see above.  It has nothing to do with Gnus.  The first
command did not bother to include minor-mode info.