 
   ## Examples
 
-      IO.write "sample"
+      IO.write("sample")
       #=> sample
 
-      IO.write :stderr, "error"
+      IO.write(:stderr, "error")
       #=> error
 
   """


  To display "What is your name?" as a prompt and await user input:

      IO.gets "What is your name?\n"

  """
  @spec gets(device, chardata | String.Chars.t()) :: chardata | nodata

  ## Examples

      stacktrace = [{MyApp, :main, 1, [file: 'my_app.ex', line: 4]}]
      IO.warn("variable bar is unused", stacktrace)
      #=> warning: variable bar is unused
      #=>   my_app.ex:4: MyApp.main/1

