I'm going through "Haskell Programming from first principles" and in section 7.3 Anonymous Functions there is an exercise on converting multiple parameters to anonymous functions, and it asks: 1. Which (two or more) of the following are equivalent? mTh1 x y z = x * y * z mTh2 x y = \z -> x * y * z mTh3 x = \y -> \z -> x * y * z mTh4 = \x -> \y -> \z -> x * y * z So I created a file, anon.hs (attached): module Anon where mTh1 x y z = x * y * z mTh2 x y = \z -> x * y * z mTh3 x = \y -> \z -> x * y * z mTh4 = \x -> \y -> \z -> x * y * z I load that into ghci and check the function types: $ ghci anon.hs GHCi, version 8.2.1: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Anon ( anon.hs, interpreted ) Ok, 1 module loaded. *Anon> :t mTh1 mTh1 :: Num a => a -> a -> a -> a *Anon> :t mTh2 mTh2 :: Num a => a -> a -> a -> a *Anon> :t mTh3 mTh3 :: Num a => a -> a -> a -> a *Anon> :t mTh4 mTh4 :: Integer -> Integer -> Integer -> Integer Why is mTh4 different from the rest? On the flip side If I enter "mTh4 = \x -> \y -> \z -> x * y * z" directly in ghci command line then it has same type as the others: $ ghci GHCi, version 8.2.1: http://www.haskell.org/ghc/ :? for help Prelude> mTh4 = \x -> \y -> \z -> x * y * z Prelude> :t mTh4 mTh4 :: Num a => a -> a -> a -> a -- Wink