Simple abstract data type exemple 1 created by essic - https://repl.it/GEaw/39

Simple abstract data type exemple 1.hs

accumulate :: (a -> b) -> [a] -> [b]
accumulate _ [] = []
accumulate f (x:xs) =  f x : accumulate f xs


data Planet = Mercury
            | Venus
            | Earth
            | Mars
            | Jupiter
            | Saturn
            | Uranus
            | Neptune


ageOn :: Planet -> Float -> Float
-- ageOn = (*) . secondsPerYear
ageOn x y = secondsPerYear x * y 

secondsPerYear :: Planet -> Float
secondsPerYear planet = earthYear * case planet of
  Mercury -> 0.2408467 
  Venus   -> 0.61519726 
  Earth   -> 1 
  Mars    -> 1.8808158 
  Jupiter -> 11.862615 
  Saturn  -> 29.447498 
  Uranus  -> 84.016846 
  Neptune -> 164.79132 
  where earthYear = 365.25 * 24 * 60 * 60

main = do
  print result
  where result = accumulate (ageOn Mars) [1,2,3,4,5]