[Haskell-beginners] invalid type signature last2::: [a] -> a

Hello, I try to solve the 99 haskell problems on several ways. But my first try which looks like this : Last2::[a]-> a Last2:: last[list] gives the following error message : src/Main.hs@1:1-1:6 Invalid type signature: Last2 :: [a] -> a Should be of form <variable> :: <type> What am trying to do is say the input is a list which can be of integers or chars so everything is the output can then also be of type everything. Roelof