bug#44270: 24.5; EMMS failures while installing

[Yoni Rabkin]

Stefan Kangas <stefan@marxist.se> writes:

> Lars Ingebrigtsen <larsi@gnus.org> writes:
>
>> John Gilmore <gnu@toad.com> writes:
>>
>>> M-x list-packages
>>> picked emms, hit Install.
>>> I've included the *Compile-Log* buffer contents, which include one
>>> error and several warnings.
>>> Compiling file /gnu/home/.emacs.d/elpa/emms-6.0/emms-browser.el at Tue Oct 
>>> 27 18:43:24 2020
>>> emms-browser.el:292:1:Error: Cannot open load file: no such file or 
>>> directory, seq
>>
>> It seems like EMMS requires seq, but that it's not installed in your
>> Emacs?  My guess is that your Emacs (24.5) is too old to use EMMS.
>>
>> But EMMS should specify that, I guess?
>
> Indeed, I think EMMS should add a dependency on seq:
>
>     ;; Package-Requires: ((cl-lib "0.5") (seq "2.22"))
>
> Perhaps it should add a dependency also on Emacs, but I don't know which
> version it would need.
>
> Yoni, could you please take a look at this?  This might warrant
> releasing a new version of the package on GNU ELPA.
>

The code which requires seq (in emms-browser.el) was added in 2017
(contemporaneous with Emacs 25.2), but of course Emacs 24.5 dates back
from 2015.

I'll see if it possible to re-write that code without seq and therefore
to regain that backward compatibility. If so, it will take a good while
before it is done.

Should I add a dependency on a particular version of Emacs in the
meantime?

-- 
   "Cut your own wood and it will warm you twice"