       iex> trunc(5.4)
       5
 
-      iex> trunc(5.99)
-      5
+      iex> trunc(-5.99)
+      -5
+
+      iex> trunc(-5)
+      -5
 
   """
   @spec trunc(value) :: value when value: integer

  end

  @doc """
  Returns the head of a list; raises `ArgumentError` if the list is empty.

  Allowed in guard tests. Inlined by the compiler.


      iex> 1 / 2
      0.5

      iex> -3.0 / 2.0
      -1.5

      iex> 5 / 1
      5.0

  """
  @spec (number / number) :: float
