diff --git a/src/lisp/test-closures.lisp b/src/lisp/test-closures.lisp
index 573024d..39bb134 100644
--- a/src/lisp/test-closures.lisp
+++ b/src/lisp/test-closures.lisp
@@ -1,12 +1,5 @@
-(defun mapcar (func list)
-  (if list
-    (cons (apply func (list (car list)))
-          (mapcar func (cdr list)))
-    nil))
-
-(defun double (n)
-  (+ n n))
-
 (defun main ()
-  (print (mapcar #'double
-                 (list 1 2 3 4 5))))
+  (print (reduce (lambda (a b)
+                   (+ a b))
+                 (list 1 2 3 4 5)
+                 0)))