anchor.diff:  
   [source,matlab]
   ----
  +% various ways to call plot
   plot(x,y);
   plot(x,y,'--rs');
   plot(x,y,'--rs', ...
  
positive.code: % common use case
  sendMessage(cmd);
  
  % expert use case
  sendMessage(cmd, 'led', led, 'gains', gains);
  ----
  
  
negative.code: * *Optional* arguments are expected after all required arguments are satisfied. An optional argument is set if its validator returns true. If the validator returns false, the parser will try the validator of the next optional argument.
  * *Parameters* are parsed last and consist of a string-key and a single corresponding value argument. They can be set in any order.
  
  Creating an inputparser looks as shown in the code below.
  
  [source,matlab]
  ----
  