code: function addReadonly (props) {
  
      return {
  
          to: function (object) {
  
              var keys = Object.keys(props);
              keys.forEach(function (key) {
  
                  Object.defineProperty(object, key, {
                      value: props[key],
                      writable: false,
                      enumerable: true,
                      configurable: false,
                  });
  
              });
  
          },
  
      };
  
  }
docs: /* Read-only property setter