I've been using Emacs hash tables a lot recently, and I would find several operations much easier if maphash returned a list. For example, I'd like to be able to do: (maphash (lambda (key value) key) some-table) to obtain the list of keys present in some-table. I would guess elisp is influenced by Common Lisp here, where maphash returns nil unconditionally. However, unlike elisp, Common Lisp's loop macro supports iterating over keys directly with (loop for key being hash-key of some-table ...) which helps considerably. I can't see any obvious way this would break backwards compatibility, so I threw together a trivial patch that makes maphash return a list of the results. I've attached the patch. Is there interest in this? Wilfred