haskell adding head and tail list code example

Example 1: first element in list haskell

list = [1, 2, 3]

head :: [a] -> a
head (x:_) = x

head list -- 1

Example 2: get tail of list haskell

list = [1, 2, 3, 4]

tail :: [a] -> [a]
tail [] = []
tail (_:xs) = xs