elisp platform-set-variable

platform-var.el

(defvar *var-plist* (list))

(defmacro platform-var (name &rest plist)
  (let ((plist-keys (mapcar 'car (seq-partition plist 2)))
        (platforms '(:gnu :gnu/linux :gnu/kfreebsd :darwin :ms-dos :windows-nt :cygwin)))
    (mapcar (lambda (key)
              (when (not (member key platforms))
                (error "Platform `%s' doesn't exist. Possible values: `%s'" key platforms)))
            plist-keys)
    (setq *var-plist* (plist-put *var-plist* name plist))
    (values)))

(defmacro platform-get (name)
  (let ((platform (intern (string-join (list ":" (symbol-name system-type))))))
    (plist-get (plist-get *var-plist* name) platform)))