Subject: Re: bug#49631: 28.0.50; dired-hide-details-mode Probably introduced at or before Emacs version 24.4

From: Stefan Kangas <[email-masked]>
Date: Wed, 29 Sep 2021 04:48:53 -0700

Lars Ingebrigtsen <[email-masked]> writes:

> Eli Zaretskii <[email-masked]> writes:
>
>>> C-h f dired-hide-details-mode says
>>>
>>>   Probably introduced at or before Emacs version 24.4.
>>>
>>> Why doesn't it _know_ precisely which versiob that function was
>>> introduced in?  It was only a few versions ago, so this was not
>>> something lost in prehistory.  What causes the uncertainty?
>>
>> The feature works by searching the etc/NEWS* files, and finding a
>> symbol there doesn't necessarily mean the Emacs release in which it's
>> mentioned is the actual release where the symbol was introduced.  For
>> example, we sometimes forget to announce features and only do that
>> later.  Thus the uncertainty and the cautious language.
>
> And Richard may not know that we've discussed, innumerable times, whether
> we should maintain an actual registry to avoid the guessing, and we've
> concluded that this would be too much work.
>
> Which is still the conclusion.

(With copy to Steve Purcell.)

Steve Purcell has some code to do this, or at least parts of it, here:

    https://github.com/purcell/package-lint/tree/master/tools

It comes out to this:

    https://github.com/purcell/package-lint/blob/master/data/stdlib-changes

Perhaps Steve would be willing to contribute his work, or even help us
integrate his tools into Emacs?