code: function () {
  
              var args = arguments,
                  argc = arguments.length;
  
              if (argc === 1) {
                  if (args[0] === undefined || args[0] === null) {
                      return undefined;
                  }
  
                  return args[0];
  
              } else if (argc === 2) {
  
                  if (args[0] === undefined || args[0] === null) {
                      return args[1];
                  }
  
                  return args[0];
  
              } else {
  
                  if (args[0][args[1]] === undefined || args[0][args[1]] === null) {
                      return args[2];
                  }
  
                  return args[0][args[1]];
              }
          }
docs: Check and get variable
  
  @returns {*}