Re: Confused by y-or-n-p

[Eli Zaretskii]

> Date: Mon, 04 Jan 2021 10:28:25 +0000
> From: Gregory Heytings <ghe@sdf.org>
> cc: emacs-devel@gnu.org
> 
>         * If some are opposed, they install the feature with a variable to 
> enable it, disabled by default. 
> 
>     This is already being done: every backward-incompatible change is either 
> required to become compatible, or, if that's not feasible, to provide a way 
> to get back the old behavior. In some rare cases this doesn't happen, but 
> such mistakes are rare exceptions, they aren't the rule.
> 
> That's not correct, see for example the thread "Stop frames stealing 
> eachothers' minibuffers!", in which the longstanding behavior of Emacs' 
> minibuffers, which are arguably a central piece of Emacs' UI, is being 
> modified on the pretext that it is "unsystematic", without any argument, and 
> in spite of the fact that hundreds and thousands of users have been using it 
> without complaining about that supposed "unsystematicity".
> 
> I repeatedly explained that the old behavior should remain available. 
> Initially the change explicitly removed the old behavior: "The old [behavior] 
> is no longer available." The latest patch sent yesterday, only promises to 
> "approximate" the old behavior.

That's because the original behavior was deemed buggy.  We don't
provide compatibility options to get old bugs back.

As it turned out, what Alan considered buggy behavior was not
necessarily so, therefore he now tries to provide a better backward
compatibility.  As the bug is still being actively worked on, it is
premature ti draw any definitive conclusions from it relevant to the
current discussion.

Also, we should recognize that some changes are deep enough to make
100% backward compatibility impractical or even infeasible.  That
doesn't mean such changes should be automatically rejected.