cluded in the array.
_.indexOf = (array, item) ->
  return array.indexOf item if nativeIndexOf and array.indexOf is nativeIndexOf
  i = 0; l = array.length
  while l - i
    if array[i] is item then return i else i++
  -1


# Provide JavaScript 1.6's **lastIndexOf**, delegating to the native function,
# if possible.
_.lastIndexOf = (array, item) ->
  return array.lastIndexOf(item) if nativeLastIndexOf and array.lastIndexOf is nativeLastIndexOf
  i = array.length
  while i
    if array[i] is item then return