:4:4: error: Couldn't match expected type ‘Ghci1.X’ with actual type ‘X’ NB: ‘X’ is defined at :3:1-25 ‘Ghci1.X’ is defined at :1:1-14 In the first argument of ‘f’, namely ‘(Y 3)’ In the expression: f (Y 3) In an equation for ‘it’: it = f (Y 3)