Type checking

2003-12-31 Thread Lee Dixon
Hi, Can anyone explain to me how hugs manages to derive that f x y z = y (y z) x is of type f :: a -> ((a -> b) -> a -> b) -> (a -> b) -> b Many thanks and a happy new year to all! Lee _ Stay in touch with absent friends - get M

Type checking/inference

2003-12-27 Thread Lee Dixon
Hi, I've run into a small problem whilst doing some manual type checking, to see if I could match the results given by hugs prelude> :t foldr filter foldr filter :: [a] -> [a -> Bool] -> [a] -- This was fine and was the same as my answer, so I tested it with prelude> foldr filter [1,2,3,4] [even