Symbol’s function definition is void: seq-keep

[jroimartin]

After updating Magit, it looks like this:

It seems that 84eaa20 causes the following error to show up:

magit-format-ref-labels: Symbol’s function definition is void: seq-keep

I followed these instructions but the problem persists.

If you have just updated Magit, then restart Emacs. If that does not fix the issue, then also uninstall Magit and all dependencies that were updated at the same time, restart Emacs and then reinstall Magit.

Magit version: Magit 20230921.2037 [>= 3.3.0.50-git], Transient 0.4.3, Git 2.41.0, Emacs 28.2, gnu/linux

[jroimartin]

As a workaround I installed seq-2.24 manually and added (require 'seq-25) to my init file. I guess this has to do with the builtin seq package (v2.23 in my case) being loaded first. I'm adding this comment here just in case it helps on debugging the issue.

[tarsius]

Last night I started using seq-keep in forge but did not add seq-2.24 as a dependency. It is possible you updated packages at this point. I then noticed the issue thanks to CI and fixed it for forge. I then went on to using seq-keep in magit as well. I did add the dependency this time around.

So it is likely that just updating packages again would also have fixed this issue; the fact that you had to manually install seq-2.24 speaks for that. If not -- if an older version of seq is being loaded, despite of the package-installed 2.24 being on the load-path -- then it is most likely an issue with package or something internal to the seq backport package itself.

[tarsius]

You should not have to manually require seq-25 because that's what the package-installed seq.el does:

[snip]
;;; Code:

(if (version< emacs-version "25")
    (require 'seq-24)
  (require 'seq-25))

(provide 'seq)
;;; seq.el ends here

[jroimartin]

I think I found the issue.

GNU Emacs 28.2 comes with seq-2.23 built in and it does not upgrade built-in packages automatically. Thus, I had to install seq-2.24 manually. Also, the function seq-keep used by magit is not autoloaded, which requires to explicitly load the library.

Long story short, my current workaround is:

1. Install seq-2.24 manually.
2. Add (load "seq") to the init file.

Does it make sense?

[jroimartin]

Information about upgrading built-in packages in GNU Emacs 29: https://git.savannah.gnu.org/cgit/emacs.git/tree/etc/NEWS.29#n1714

[tarsius]

I've added an explicit require.

(You shouldn't use load. It is almost always better to use require.)

I'll have to look into those news. I don't use package myself, and assume(d) that it does not silently ignore explicitly specified dependency versions (by default, or ever).

[jroimartin]

However, I cannot use (require 'seq) because it seems the feature seq is already provided by /usr/share/emacs/28.2/lisp/emacs-lisp/seq.elc (instead of ~/.emacs.d/elpa/seq-2.24/seq.el) by the time it is called from my init file. So require is ignored.

[tarsius]

I see. That probably means that something loads seq before package-initialize is called. Across Emacs releases, there are big difference in how and when that is automatically called for you, if at all, how you can call it explicitly instead, and what the recommended way of doing that is. It could be that this defaults to being broken, but it could also could be that you do something that results in this behavior (possibly because it at one point was recommended that you do that).

In other words I will have to investigate. Meanwhile, other users running into this, should first try to update, and if that alone doesn't work add (require 'seq) explicitly early on (but after package-initialize, if that can be found in early-init.el or init.el), and only if that also doesn't work, fall back to (load 'seq).

If this is indeed a bug causes by the default configuration of some Emacs releases, or a common misconfiguration, then I might have to require seq like so:

(when (and (featurep' seq)
          (not (fboundp 'seq-keep)))
  (unload-feature 'seq 'force))
(require 'seq)

[makohoek]

@jroimartin thank you for opening this. I confirm your work-around works for me as well. I'm also on emacs 28.2.

I've made a similar hack in my spacemacs config here:
makohoek/dotfiles@c7868f9

[RastaDill]

Hello. Does anyone know how to install the previous version of the package?
Why used rolling release?

[qezz]

As a short-term solution, it's possible to have the seq-keep definition in init.el

(defun seq-keep (function sequence)
  "Apply FUNCTION to SEQUENCE and return the list of all the non-nil results."
  (delq nil (seq-map function sequence)))

(from https://github.com/emacs-mirror/emacs/blob/master/lisp/emacs-lisp/seq.el)

After this, magit works fine.

[tarsius]

I've installed the mentioned kludge.

[doolio]

Just ran into this issue. Uninstalling magit and its dependencies and re-installing doesn't install the latest version of the seq package. I use straight.el rather than package.el if that matters and am still on Emacs 27.1. The workaround mentioned here is working for me though.

[tarsius]

@doolio You should probably report that to Straight's maintainers.

[tarsius]

Straight does not update dependencies and even ignores the specified minimal versions. See radian-software/straight.el#1083.

[doolio]

Straight does not update dependencies and even ignores the specified minimal versions.

The latest commit on straight's develop branch fixes this issue wrt magit at least.

[spacekookie]

I ran into this issue again on magit version 20231112.914. I'm installing emacs and dependencies via nix, so manually side-loading seq isn't an option. But I thought it also wouldn't be required anymore in this version?

[tarsius]

But I thought it also wouldn't be required anymore in this version?

Magit now works around deficits of package.el, but that doesn't change the fact that it depends on seq v2.24, which means that that package has to be installed independently when using an Emacs release that does not include that version yet.

I ran into this issue again on magit version 20231112.914. I'm installing emacs and dependencies via nix, so manually side-loading seq isn't an option.

That's a bug in how magit is packages in nix then. Please report this to the maintainer of magit in nix. Thanks!

[Nebucatnetzer]

I ran into this issue again on magit version 20231112.914. I'm installing emacs and dependencies via nix, so manually side-loading seq isn't an option. But I thought it also wouldn't be required anymore in this version?

Do you have by chance a workaround for a Nix based config?
Edit: I installed the package from melpa for the moment until the package gets fixed in Nix or there is a known workaround.

[mmarx]

I ran into this issue again on magit version 20231112.914. I'm installing emacs and dependencies via nix, so manually side-loading seq isn't an option. But I thought it also wouldn't be required anymore in this version?

Do you have by chance a workaround for a Nix based config?

This is what I'm currently using:

  overrides = self: super: {
    elpaPackages =
      super.elpaPackages
      // {
        seq = self.callPackage ({
          elpaBuild,
          fetchurl,
          lib,
        }:
          elpaBuild rec {
            pname = "seq";
            ename = "seq";
            version = "2.24";
            src = fetchurl {
              url = "https://elpa.gnu.org/packages/seq-2.24.tar";
              sha256 = "1w2cysad3qwnzdabhq9xipbslsjm528fcxkwnslhlkh8v07karml";
            };
            packageRequires = [];
            meta = {
              homepage = "https://elpa.gnu.org/packages/seq.html";
              license = lib.licenses.free;
            };
            # tests take a _long_ time to byte-compile, skip them
            postInstall = ''rm -r $out/share/emacs/site-lisp/elpa/${pname}-${version}/tests'';
          }) {};
      };
  };

emacsPackage =
    ((pkgs.emacsPackagesFor pkgs.emacs29-gtk3).overrideScope' overrides).emacsWithPackages …;`

[crawford]

Thanks for the hint @mmarx. I've adapted it for Home Manager in case anyone is looking for that as well:

{
  programs = {
    emacs = {
      overrides = self: super: rec {
        # Taken from https://github.com/magit/magit/issues/5011#issuecomment-1838598138
        seq = self.callPackage ({ elpaBuild, fetchurl, lib }:
          elpaBuild rec {
            pname = "seq";
            ename = "seq";
            version = "2.24";
            src = fetchurl {
              url = "https://elpa.gnu.org/packages/seq-2.24.tar";
              sha256 = "1w2cysad3qwnzdabhq9xipbslsjm528fcxkwnslhlkh8v07karml";
            };
            packageRequires = [];
            meta = {
              homepage = "https://elpa.gnu.org/packages/seq.html";
              license = lib.licenses.free;
            };
            # tests take a _long_ time to byte-compile, skip them
            postInstall = ''rm -r $out/share/emacs/site-lisp/elpa/${pname}-${version}/tests'';
          }) {};
      };
    };
  };
}