主要是怎么把原来有的对象集合和分页新获取的对象 集合concat在一起

wx.request({

      url: url + ‘/product1!allajproduct1.action？page=’ + page,

      method: ‘get’,

      header: { ‘Content-Type’: ‘application/json’ },

      success: function (res) {

        console.log(‘res.data’ + res.data[1]);

        Lsit = list.concat(res.data)

        that.setData({

          page: that.data.page + 1,

          product1s: Lsit,

        });

      },

      fail: function (res) {

        console.log(‘submit fail’);

      },

      complete: function (res) {

        console.log(‘submit complete’);

      }

    }) 

我这代码总是报

list.concat is not a function;at pages/allproducts/allproducts onReachBottom function;at api request success callback function

TypeError: list.concat is not a function

这个错误 求大神指教