anchor.diff:  		_Pattern =  jsonschema:keyword(Schema,"pattern"),  %% to be added later
   
   	    case MinLength of 
  +
   			undefined -> 
   				Min = 0;
  +
   			_ -> 
   				Min = MinLength
   	    end,
  
positive.code:     %% TODO: generator for array (no items)
      %% (it could be integrated in array/1)
      null().
  
negative.code: 	    case MaxLength of
  
  			undefined ->
  				Max = ?MAX_STR_LENGTH; 
  
  			_ ->  
  				Max = MaxLength
  		end,			
  	    
  
  		?LET(Rand,randInt(Min,Max), 
  			?LET(S, stringGen(Rand), list_to_binary(S)));
  		
  
  
  