SLY: Make pure environment usable by preserving some more variables.

.emacs.d/lisp/init-sly.el

@@ -1,5 +1,17 @@
 (require 'patch-sly)
 
+(defun pure-env (&rest preserve-vars)
+  "Return a pure `env' command as a list of string."
+  (append '("env" "-i")
+          (mapcar (lambda (var) (concat var "=" (getenv var)))
+                  (append
+                   '("DISPLAY"
+                     "HOME"
+                     "LOGNAME"
+                     "TERM"
+                     "USER")
+                   preserve-vars))))
+
 (defun ambrevar/sbcl-for-nyxt (&optional refresh) ;; TODO: Run it in a container?
   "Fast, pure Guix environment for Nyxt development.
 If REFRESH is non-nil, rebuild the environment."
@@ -25,7 +37,7 @@ If REFRESH is non-nil, rebuild the environment."
         ;; Update root mtime in case it's not changed.
         ;; Can't use `set-file-times' on links.
         (call-process "touch" nil nil nil "-h" root))
-      `(("env" "-i" ,(concat "HOME=" (getenv "HOME")) ; HOME is needed for the ASDF cache.
+      `((,@(pure-env "PERSONAL")
          ,(executable-find "bash") "--norc" "--noprofile" "-c"
          ,(concat (format "source '%s/etc/profile'" root)
                   " && sbcl"))))))