anchor.diff:  * *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 a parser looks as shown in the code below.
  +Creating an inputparser looks as shown in the code below.
   
   [source,matlab]
   ----
  
positive.code: * Error messages become less useful for cases with non-trivial validation
  * There are methods with >20 parameters, at which point this approach becomes unmaintainable and actually degrades performance.
  
  Thus, we ended up implementing our own input parser equivalent entirely behind the language barrier.
  
  == Custom InputParser
  
  === varargin
  
  
negative.code: 
  [source,matlab]
  ----
  % various ways to call plot
  plot(x,y);
  plot(x,y,'--rs');
  plot(x,y,'--rs', ...
  