bug#23184: 25.0.92; User-friendly way to override doc-view-mode as MIME viewer

[Tassilo Horn]

Hi Teemu and Eli,

that's exactly my intention: have a simple way to override emacs heuristic 
choices in case where they don't match the user's expectations. So in your 
case, you'd be fine with just a single entry for application/pdf and your 
preferred viewer.

The problem with an option to simply use ~/.mailcap is that in there, you 
cannot use emacs viewers at all.

Bye,
Tassilo


Am 9. April 2016 11:47:50 schrieb Eli Zaretskii <eliz@gnu.org>:

> > From: Teemu Likonen <tlikonen@iki.fi>
> > Date: Sat, 09 Apr 2016 12:27:38 +0300
> > Cc: 23184@debbugs.gnu.org
> >
> > > (2) Or maybe we could add a customizable list `mailcap-user-mime-data'
> > >     (better name welcome) which would override `mailcap-mime-data',
> > >     i.e., if a viewer is specified there, then `mailcap-mime-data' with
> > >     the heuristics around it won't even be consulted.
> >
> > > Any better suggestions?  If not, I can do that.  (In case I'd implement
> > > that, should that go only into master or emacs-25?)
> >
> > I don't oppose mailcap-user-mime-data but I think user shouldn't be
> > forced to duplicate his mailcap configuration inside Emacs.
>
> Does that suggestion really require duplication, or does it require to
> have only those (hopefully few) entries that override the default?
>
> > User already has his system's mailcap settings and many programs
> > respect that. Why doesn't Emacs? (Ok, it does but with its own
> > preferences of doc-view-mode etc.)
>
> Because doc-view-mode is specific to Emacs?
>
> > How about a variable like mailcap-prefer-system-mailcap with a non-nil
> > value would put the priority of doc-view-mode (and every viewer Emacs
> > offers) below system's mailcap configuration?
>
> That'd still require a separate customization in Emacs, so I wonder
> how it is better than what Tassilo proposed.