:2:5: error: You can't mix polymorphic and unlifted bindings: a = (# 1 #) Probable fix: add a type signature :3:5: error: You can't mix polymorphic and unlifted bindings: a = (# 1, 3 #) Probable fix: add a type signature :1:1: error: GHCi can't bind a variable of unlifted type: a :: (# Integer, Integer #)