@@ -182,9 +182,10 @@ contain the new value at the location focused by the lens."

   (lambda (cb)

     (lambda (old-hash)

       (fmap (lambda (new)

-              (fw.lu:prog1-bind (new-hash (alexandria:copy-hash-table old-hash))

-                (setf (gethash key new-hash)

-                      new)))

+              (let ((new-hash (alexandria:copy-hash-table old-hash)))

+                (prog1 new-hash

+                  (setf (gethash key new-hash)

+                        new))))

             (funcall cb (gethash key old-hash))))))

 ;; imagine a lens here that uses the MOP to immutably update a class...

@@ -498,6 +499,7 @@ contain the new value at the location focused by the lens."

                           it

                           (alexandria:iota it-length))))))))

+#+nil

 (defmacro <> (arity &rest funs)

   (let ((arg-syms (loop repeat arity collect (gensym))))

     `(lambda (,@arg-syms)

@@ -510,4 +512,4 @@ contain the new value at the location focused by the lens."

                            arg-syms))))

 (defmacro <>1 (&rest funs)

-  `(<> 1 ,@funs))

+  `(alexandria:compose ,@funs))