Haskell inheritance, data, constructors

Question

So I want to define multiple data classes for my Asteroids game/assignment:

data One = One {oneVelocity :: Velocity, onePosition :: Position, (((other proper         


        

Answer 1

You should probably use just a single data type for all of these, but parameterised on the specific details:

data MovingObj s = MovingObj
        { velocity :: Velocity
        , position :: Position
        , specifics :: s }

Then you can create e.g. asteroid :: MovingObj AsteroidSpecifics, but you can also write functions that work with any such moving object like

advance :: TimeStep -> MovingObj s -> MovingObj s
advance h (MovingObj v p s) = MovingObj v (p .+^ h*^v) s