impls/lib/load-file-once.mal

   1 ;; Like load-file, but will never load the same path twice.
   2
   3 ;; This file is normally loaded with `load-file`, so it needs a
   4 ;; different mechanism to neutralize multiple inclusions of
   5 ;; itself. Moreover, the file list should never be reset.
   6
   7 (def! load-file-once
   8   (try*
   9     load-file-once
  10   (catch* _
  11     (let* [seen (atom {"../lib/load-file-once.mal" nil})]
  12       (fn* [filename]
  13         (if (not (contains? @seen filename))
  14           (do
  15             (swap! seen assoc filename nil)
  16             (load-file filename))))))))