:: [Int] -> Int package:base-prelude

last :: [a] -> a
base-prelude BasePrelude
Extract the last element of a list, which must be finite and non-empty.
head :: [a] -> a
base-prelude BasePrelude
Extract the first element of a list, which must be non-empty.
mconcat :: Monoid a => [a] -> a
base-prelude BasePrelude
Fold a list using the monoid. For most types, the default definition for mconcat will be used, but the function is included in the class definition so that an optimized version can be provided for specific types. 
>>> mconcat ["Hello", " ", "Haskell", "!"]
"Hello Haskell!"