Re: yank-media: allow users to limit image types that can be inserted

[Eli Zaretskii <eliz@gnu.org>]

> From: Visuwesh <visuweshm@gmail.com>
> Cc: rpluim@gmail.com,  pinmacs@cas.cat,  emacs-devel@gnu.org
> Date: Tue, 24 Sep 2024 10:30:49 +0530
> 
> [திங்கள் செப்டம்பர் 23, 2024] Eli Zaretskii wrote:
> 
> >> AFAIR the yank-media code, there's no way for the handlers to reject a
> >> specific format.  yank-media, the command, asks the user the type she
> >> wants, _then_ calls the handler specific to that type.  The handler
> >> cannot influence anything during this interaction.
> >
> > This is true, but I don't see how it is relevant to what I suggested.
> 
> I was replying to this part:
> 
>     The issue at hand here, AFAIU, is not the UI, but how Lisp programs
>     (and Org in particular) can control this.
> 
> My point was that there is little control over this UI from the handlers
> type since the handler cannot filter the types available.

OK, but then my point was that a Lisp program _can_ control this by
customizing the list of handlers.  It could even replace all the
handlers with its own single handler, which could then call the other
handlers according to some logic, thus working around the fact that
there's no mechanism currently for a handler to refuse to handle the
type for which it is registered.