Has anyone made a program for Hugs that allows you to add type definitions and top level functions to the Main module from the interpreter command line? I find it odd that I have load from a text file to experiment with data types, classes, etc. If this sort of thing is not available convince me either to: a) write one myself or b) don't waste my time. This is what a session might look like: Main> data List a = Cons a | Nil deriving Show -- type constructor data List a -- constructors: Cons :: a -> List a -> List a Nil :: List a -- instances: instance Show a => Show (List a) Main> (Cons (Cons 4 Nil) Nil) Cons (Cons 4 Nil) Nil Main> data List = Dummy -- type constructor data List -- constructors: Dummy :: List Main> (Cons 4 Nil) ERROR - Undefined constructor function "Nil" Eric Wohlstadter UCDavis Software Tools Lab