code: function (options) {
          if (!_.isObject(options)) {
              return;
          }
          // set type and value.
          // @note that we cannot update the key, once created during construction
          options.hasOwnProperty('type') && this.valueType(options.type, options.hasOwnProperty('value'));
          options.hasOwnProperty('value') && this.set(options.value);
          options.hasOwnProperty('system') && (this.system = options.system);
          options.hasOwnProperty('disabled') && (this.disabled = options.disabled);
      }
docs: Updates the type and value of a variable from an object or JSON definition of the variable.
  
  @param {Variable~definition} options