Pierwszy element z listy Haskell
list = [1, 2, 3]
head :: [a] -> a
head (x:_) = x
head list -- 1
Hippo_error
list = [1, 2, 3]
head :: [a] -> a
head (x:_) = x
head list -- 1a = [1, 2, 3, 4]
b = tail a
-- b == [2, 3, 4]