久しぶりのランチタイム勉強 #CodePiece

CodePiece.hs

-- data Person = Person String String Int Float String String deriving (Show)
  
data Person = Person { firstName :: String,
                       lastName :: String, 
                       age :: Int, 
                       height :: Float,
                       phoneNumber :: String,
                       flavor :: String
                       } deriving (Show)

data Car = Car { company :: String,
                 model :: String,
                 year :: Int
                 } deriving (Show)

data IntMayby a = INothing | IJust Int

-- データ宣言には型クラス制約をつけない
data Vector a = Vector a a a deriving(Show)

-- 関数の型宣言で制約を付与する
vplus :: (Num a) => Vector a -> Vector a -> Vector a
(Vector i j k) `vplus` (Vector l m n) = Vector (i+l) (j+m) (k+n)

dotProd :: (Num a) => Vector a -> Vector a -> a
(Vector i j k) `dotProd` (Vector l m n) = (i*l) + (j*m) + (k*n)

vmult :: (Num a) => Vector a -> a -> Vector a
(Vector i j k) `vmult` m = Vector (i*m) (j*m) (k*m)