==> (set! fact (lambda (n) (if (= n 0) 1 (* n (fact (- n 1)))))) (EXCL::.LEXICAL-CLOSURE. (LAMBDA (&REST ARGS) (INTERP CODE (NCONC (MAPCAR (FUNCTION LIST) VARS ARGS) ENV))) ((CODE BEGIN (IF (= N 0) 1 (* N (FACT (- N 1))))) (VARS N) (ENV) (PARAMS (N) (IF (= N 0) 1 (* N (FACT (- N 1))))) (NAME . LAMBDA)) NIL ((SCHEME-SPECIAL-FORM-INTERP . EXCL::INVALID)) NIL) ==> (fact 5) 120