anchor.diff:  
   <<Static Version Information,Version help>> may have format specifiers that format additional arguments passed to the `printVersionHelp` method.
   
  -See the https://docs.oracle.com/javase/8/docs/api/java/util/Formatter.html[java.util.Formatter javadoc] for details.
  +See the https://docs.oracle.com/javase/8/docs/api/java/util/Formatter.html[java.util.Formatter JavaDoc] for details.
   
   IMPORTANT: Note that to show percent `'%'` characters in the usage help message, they need to be escaped with another `%`. For example: `@Parameters(description = "%%-age of the total")` is rendered as `%-age of the total`.
   
  
positive.code: 
  
  ==== Maps
  Picocli 1.0 introduced support for `Map` fields similar to Java's system properties `-Dkey=value` or Gradle's project properties `-Pmyprop=myvalue`.
  
  `Map` fields may have any type for their key and value
  as long as a <<Strongly Typed Everything,converter>> is registered for both the key and the value type.
  
negative.code:     String y;
  
      // reset to null when option not specified
      @Option(names = "-x", defaultValue = Option.NULL_VALUE)
      void setX(String x) { this.x = x; }
  
      // retains value of previous parseArgs invocation when option not specified
      @nption(names = "-y")
      void setY(String y) { this.y = y; }
  }
  ----
  