[Haskell-cafe] how do I avoid excessive constructor application?

For some reason, these two functions have different types. fun1 f (Left x)= Left (f x) fun1 _ r@(Right x) = Right x fun2 f (Left x) = Left (f x) fun2 _ r = r Is there a way to rewrite fun2 so that f has type (a->b)? In the general case, it seems wasteful to have to destruct and construct values just for type checking reasons, especially if your type has many more constructors than (Either a b). -Alex- ______________________________________________________________ S. Alexander Jacobson tel:917-770-6565 http://alexjacobson.com