Drop Emacs 25 support?

[minad]

This version is currently available on stable Debian (buster). Furthermore there is also an official 27.1 backport now available in buster-backports. Both Consult and Embark already require 26.1. Some of the popular distributions like Doom even seem to move away from 26. See also https://www.gnu.org/software/emacs/history.html.

[clemera]

I also see no problems to drop it as soon as we have code which would need backward compatibility checks, for now it doesn't seem to harm to keep it or do you have something in mind?

[clemera]

Do you know if Doom is considering using Selectrum? I have heard there is some interest but I have no details.

[minad]

I also see no problems to drop it as soon as we have code which would need backward compatibility checks, for now it doesn't seem to harm to keep it or do you have something in mind?

Well, I drop support as soon as I cannot test it anymore without major effort. But I am not very conservative here, maybe @raxod502 wants to keep longer backward compatibility. I noticed when editing the Selectrum code, that I could not write certain things, e.g, when-let*. I am unsure which other incompatibilities are lurking somewhere else. In Consult I also had Emacs 26 related bugs (https://github.com/minad/consult/blob/9b078f5c981feefb3eab8648baf3047bf8aab33c/consult.el#L542). This particular bug I consider to be rather severe, even if the reason for the bug is trivial. If I find bugs like this I somehow lose the trust in the given version and have the urge to move on more quickly. Emacs 27 in contrast seems to be rock solid. I have found no problems with it, except this hook memory issue. But to be fair, this is not yet fixed in 28 and the bug has been present for a very long time.

Do you know if Doom is considering using Selectrum? I have heard there is some interest but I have no details.

Yes it is. See doomemacs/doomemacs#4664. I am unsure about the opinion of the maintainers, but there are some interested folks, who already seem to be using it. I personally have not tried Doom+Selectrum. But I am usually using my own minimal config. I still find it interesting how well everything works out in a more involved setting with many packages.

[clemera]

Great, I also haven't tried Doom but it certainly looks like a nice distribution. I also noticed the problem with when-let* in the past I agree that it would be nice to be able to use it.

[bdarcus]

I am unsure about the opinion of the maintainers ...

FWIW, he weighed in here, and so certainly seems open to it, though notes there's work to be done to cover all the functionality of the ivy module:

doomemacs/doomemacs#4519 (review)

[minad]

Regarding the Emacs 25 issue, I think it makes sense drop 25 as soon as we go on with the removal of the deprecated functionality present in 3.1. I am unsure when you want to make this cut in the master branch, maybe in a month or two to give people using Selectrum master time to adapt. Note that I did this superficial search on github for selectrum-read usage (#443) and fortunately not much turned up. The most serious one being amx, but I suppose the fix there will be merged soon.

[raxod502]

Doom only supports 26.3+, so I don't think there is any trouble with that for dropping support for Emacs 25. I have no hard rule for when to drop support for an old version, although I think it is important to maintain support at least for the version of Emacs that is shipped with the most recent Ubuntu LTS release. Dropping support when it becomes inconvenient to maintain for whatever reason is reasonable.