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:info
Prelude> :info Ordering
data Ordering = LT | EQ | GT -- Defined in GHC.Ordering
instance Bounded Ordering -- Defined in GHC.Enum
instance Enum Ordering -- Defined in GHC.Enum
instance Eq Ordering -- Defined in GHC.Base
instance Ord Ordering -- Defined in GHC.Base
instance Read Ordering -- Defined in GHC.Read
instance Show Ordering -- Defined in GHC.Show
head, last, tail
Prelude> head [1,2,3]
1
Prelude> last [1,2,3]
3
Prelude> tail [1,2,3]
[2,3]Prelude> let add_all xs = if null xs then 0 else (head xs) + add_all(tail xs)
Prelude> add_all [1..10]
55
fst, snd
Prelude> fst (1, 2) 1 Prelude> snd (1, 2) 2 |haskell|< ** map >|haskell| Prelude> :type map map :: (a -> b) -> [a] -> [b] Prelude> map log [1..3] [0.0,0.6931471805599453,1.0986122886681098] Prelude> map exp [1..3] [2.718281828459045,7.38905609893065,20.085536923187668] Prelude> map ((*) 3) [1..3] [3,6,9]