實現對象數組的扁平化處理？

const data = [{
   name: "撤回",
   type: "withdraw"
}, {
   name: "...",
   type: "other",
   children: [{
      name: "會簽",
      type: "sign"
   }]
}];

const flat = data.reduce((pre, cur) => {
   return cur.children ? pre.concat(cur.children) : pre.concat(cur);
}, []);

打印結果

[ { name: '撤回', type: 'withdraw' },

{ name: '會簽', type: 'sign' } ]