Dear all, I have a question about evaluation with respect to types and currying. Consider this programm: import Debug.Trace -- add :: Integer -> Integer -> Integer add :: Int -> Int -> Int add x y = x + y f a b c = trace "b" (add x c) where x = trace "a" (add a b) main :: IO () main = do print (f 1 2 3) print (f 1 2 4) Compiled with ghc-7.0.3: $ ghc --make Main.hs -o main -O2 The function add has to types. When we use type Int -> Int -> Int, the programm produces "b a 6 b a 7" as output which shows that the x from the where clause in f is evaluated twice. However, when we use type Integer -> Integer -> Integer, this will give "b a 6 b 7" which shows that x is evaluated only once. This was rather unexpected to me. Why does the number of evaluation steps depend on a type? Can anybody explain this or give a hint? Thank you very much, Heinrich -- -- hoerdegen@funktional.info www.funktional.info --