!! package:numeric-prelude

(!!) :: [a] -> Int -> a
numeric-prelude NumericPrelude NumericPrelude.Base
List index (subscript) operator, starting from 0. It is an instance of the more general genericIndex, which takes an index of any integral type.
(!!) :: C n => [a] -> n -> a
numeric-prelude NumericPrelude.List.Checked NumericPrelude.List.Generic
The index must be smaller than the length of the list, otherwise the result is undefined.