Defining a function signature in Haskell's interpreter GHCi doesn't work. Copying an example from this page:
Prelude> square :: Int -> Int
<interactive>:60:1: error:
• No instance for (Show (Int -> Int)) arising from a use of ‘print’
(maybe you haven't applied a function to enough arguments?)
• In a stmt of an interactive GHCi command: print it
Prelude> square x = x * x
How can I declare a function signature and then give function definition in Haskell interactively? also: why can't I simply evaluate the function and see its type (e.g. Prelude> square) once it has been defined?