tail-recursive sum in Erlang and LFE

example.erl

sum(L) -> sum(L,0).
sum([], Total) -> Total;
sum([H|T], Total) -> sum(T, H+Total).

sum.lfe

(defun sum (l) (sum l 0))
(defun sum
  (('() total) total)
  (((cons h t) total) (sum t (+ h total))))

; or using a ``cons`` literal instead of the constructor form:

(defun sum (l) (sum l 0))
(defun sum
  (('() total) total)
  ((`(,h . ,t) total) (sum t (+ h total))))