added rev

2 files changed, 10 insertions, 0 deletions

diff --git a/hofs.lisp b/hofs.lisp
index 7f7afce..e8bdbc4 100644
--- a/hofs.lisp
+++ b/hofs.lisp
@@ -27,3 +27,12 @@ returning a list of return values."
   (lambda (&rest args)
     (loop :for fn :in (cons fn1 fns)
           :collect (apply fn args))))
+
+
+(defun rev (fn)
+  "Return a function that applies its arguments to FN in reverse order.
+
+E.g. (funcall (rev #'cons) 1 2)  ;; (2 . 1)"
+  (lambda (&rest args)
+    (apply fn (reverse args))))
+
diff --git a/package.lisp b/package.lisp
index 45c1374..280a253 100644
--- a/package.lisp
+++ b/package.lisp
@@ -4,5 +4,6 @@
   (:use #:cl)
   (:export #:closure
            #:mapped
+           #:rev
            #:lambda-if
            #:lambda-cond))