bug#44726: 28.0.50; [feature/native-comp] Provide a mechanism to populate comp-eln-load-path from the environment

[Andrea Corallo]

Tad <tadfisher@gmail.com> writes:

> Emacs populates `load-path' at startup from `$EMACSLOADPATH' in the
> process environment. It would be useful to have an
> `$EMACSNATIVELOADPATH' or equivalent to populate `comp-eln-load-path'.
>
> I have implemented a workaround in NixOS with some code in
> `site-start.el', but it would probably be useful in other contexts as
> well.
>
>     ;; Append paths set via `EMACSNATIVELOADPATH', an environment
>     ;; variable made up for this purpose.
>     (when-let ((path-env (getenv "EMACSNATIVELOADPATH"))
>                (paths-from-env (split-string path-env))
>                (paths (seq-filter (lambda (path) (not (string= "" path)))
>                                   paths-from-env)))
>       (setq comp-eln-load-path
>             (append paths comp-eln-load-path)))

Wouldn't EMACS_NATIVE_LOAD_PATH be more idiomatic?

  Andrea