code: function modAddDefinedListener( id, listener, lowPriority ) {
          if ( modIsDefined( id ) ) {
              listener( id );
              return;
          }
  
          var listeners = modDefinedListener[ id ];
          if ( !listeners ) {
              listeners = modDefinedListener[ id ] = [];
          }
  
          lowPriority
              ? listeners.unshift( listener )
              : listeners.push( listener );
      }
docs: 添加模块定义监听器
  
  @ignore
  @param {string} id 模块标识
  @param {Function} listener 模块定义监听器
  @param {boolean} lowPriority 是否低优先级触发