:: [a] -> Int -> a package:termonad

List index (subscript) operator, starting from 0. It is an instance of the more general genericIndex, which takes an index of any integral type.
>>> ['a', 'b', 'c'] !! 0
'a'

>>> ['a', 'b', 'c'] !! 2
'c'

>>> ['a', 'b', 'c'] !! 3
*** Exception: Prelude.!!: index too large

>>> ['a', 'b', 'c'] !! (-1)
*** Exception: Prelude.!!: negative index
WARNING: This function is partial. You can use <atMay https://hackage.haskell.org/package/safe-0.3.19/docs/Safe.html#v:atMay> instead.