Haskell: Data type containing other Data Types

Question

if I have two data structures

data Tri = Tri {a :: Int, b :: Int , c :: Int} deriving Show
data Quad = Quad {w :: Int, x :: Int, y :: Int, z :: Int} deriving Sh         


        

Answer 1

You have to give names to data constructors:

data Shape = ShapeTri  { shapeTri  :: Tri }
           | ShapeQuad { shapeQuad :: Quad } 
                 deriving Show