0.hs

Prelude> let sum x y = x + y
Prelude> :type sum
sum :: Num a => a -> a -> a

1.hs

Prelude> let f = sum 3
Prelude> :type f
f :: Integer -> Integer
Prelude> f 4
7

2.hs

Prelude> let double = (* 2)
Prelude> :type double
double :: Integer -> Integer
Prelude> :type (2 ^)
(2 ^) :: (Integral b, Num a) => b -> a

3.hs

Prelude> :type map (+ 1)
map (+ 1) :: Num b => [b] -> [b]
Prelude> :type map (\x -> x + 1)
map (\x -> x + 1) :: Num b => [b] -> [b]

4.hs

Prelude> let s = foldl (+) 0
Prelude> :type s
s :: [Integer] -> Integer

5.hs

Prelude> let prod xs = foldl (*) 1 xs
Prelude> prod [1, 2, 3, 4]
24

6.hs

Prelude> let prod = foldl (*) 1
Prelude> prod [1, 2, 3, 4]
24

7.hs

Prelude> :type "hello"
"hello" :: [Char]
Prelude> :kind [Char]
[Char] :: *

8.hs

Prelude> :kind Either
Either :: * -> * -> *
Prelude> :kind Either String
Either String :: * -> *
Prelude> :kind Either String Int
Either String Int :: *