anchor.diff:      width of the current Kakoune window
   
   Values in the above list that do not mention a context are available
  -everywhere. Values that mention "buffer scope" are also available in window
  -scope.
  +everywhere.
   
   A value described as a "quoted list" will follow the rules of Kakoune string
   quoting (See <<command-parsing#,`:doc command-parsing`>>). An "unquoted list"
  
positive.code:     the complete parameter string of the executing hook
  
  *%val{modified}*::
      _in buffer scope_ +
      `true` if the buffer has modifications not saved, otherwise `false`
  
  *%val{register}*::
  
negative.code:     the text entered by the user in response to the `prompt` command
  
  *%val{timestamp}*::
      _in buffer, window scope_ +
      timestamp of the current buffer, an integer that increments each time the
      buffer is modified, including undoing and redoing previous modifications
      (see also `%val{history_id}`)
  