[bug#64620] [PATCH] gnu: home: Add home-emacs-service-type.

[Liliana Marie Prikler <liliana.prikler@gmail.com>]

Hi, Kierin

Am Donnerstag, dem 12.10.2023 um 18:15 -0400 schrieb Kierin Bell:
> […]
> The benefits are maintainability and usability --- users who don't
> want to use the package configuration interface don't have to deal
> with the cognitive dissonance.
> 
> The downside is that Emacs package configuration becomes more
> cumbersome for more advanced use cases.
> 
> One case, illustrated above, is that the
> `home-emacs-packages-service-type' doesn't know the Emacs version
> used by the `home-emacs-service-type' --- a non-default version of
> Emacs must be specified again, separately, for the packages service
> (that is, if it matters that the package serializer knows the Emacs
> version).
> 
> Another case is that in order to configure Emacs packages for
> specific Emacs servers (created via the `servers' field of the
> `home-emacs-configuration'), there would either need to be a
> `servers' field in the `home-emacs-packages-configuration' record
> type (complicated to implement) or users would need to do this
> manually (with the help of a new function such as `emacs-server-with-
> packages').
> 
> I'd appreciate hearing preferences or arguments for or against
> either. Also, suggestions for simplifying any part of the interface
> are welcome!
I think you should separate your concerns more clearly.  Rather than
having home-emacs-service-type take packages and all that other fluff,
you could just have init-directory as a list of file-likes.  Then you
can have an init.el-file procedure (or syntax) to take care of
packages.

e.g.
  (home-emacs-configuration
    (emacs %my-custom-emacs)
    (init-directory
      (list (init.el-file (emacs-package …) (elisp* …) …))))
Now, admittedly, snarfing guix packages out of init.el-file might
become an issue; I haven't thought about how to implement that
concretely.

The upside is, that you could reuse this structure for servers.  An
emacs-server would just take another home-emacs-configuration and a
server name.

Cheers