anchor.diff:  == Required Arguments
   === Required Options
   Options can be marked `required` to make it mandatory for the user to specify them on the command line. When a required option is not specified, a `MissingParameterException` is thrown from the `parse` method. For example:
  -[source, java]
  +
  +.Java
  +[source,java,role="primary"]
   ----
   class MandatoryOption {
       @Option(names = "-n", required = true, description = "mandatory number")
  
positive.code:     int number;
  }
  ----
  The following command line arguments would result in an exception complaining that `files` are missing:
  ----
  // invalid: missing file parameters
  
negative.code:     File[] files;
  }
  ----
  
  .Kotlin
  [source,kotlin,role="secondary"]
  ----
  class MandatoryOption {
      @Option(names = ["-n"], required = true, description = ["mandatory number"])
      var number = 0
  
      @Parameters
      lateinit var files: Array<File>
  }
  ----
  
  The following command line arguments would result in an exception complaining that `number` is missing:
  ----
  // invalid: missing option -n
  