bug#51523: 29.0.50; gnus-mime-view-part-externally very slow

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: gregory@heytings.org,  51523@debbugs.gnu.org,  monnier@iro.umontreal.ca
> Date: Mon, 01 Nov 2021 18:23:16 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > My point is that saying "this is what I want" is not a good argument
> > for deciding what a general-purpose function should and shouldn't do.
> 
> Well, we're the Emacs maintainers, so "what a maintainer wants" is pretty
> much how we design general-purpose functions, isn't it?

Presumably, Emacs maintainers have some general-purpose use case or
set of use cases in their minds when they design this stuff, don't
they?  That's why I asked what would those use cases be in this case;
"this is what I want" doesn't really answer that question, and doesn't
allow to have a discussion about what is and isn't TRT for this
function to do.

It's okay to have special-purpose functions when that's convenient,
but then we shouldn't put this in files.el and shouldn't advertise it
as a general-purpose function.