es7 数组解构输出对象

/**
* const arr = [[100,200,300],[1,2,3]];
 * 期望数据格式：
 * [
  *  {key: 0, piece: 100,amount:200, sum: 300},
  *  {key: 1, piece: 1,amount:2, sum: 3}
 * ]
*/
let newPoints = arr.map(([piece,amount,sum],index)=>{
  //1.传入解构 [piece,amount,sum] = [100,200,300]
   //2.piece = 100,amount=200, sum = 300
   //3.return {piece:piece,amount:amount,sum:sum} 简写 return {piece,amount,sum}
  return {key:index,piece,amount,sum};
})
console.log('newPoints',newPoints)	
//[{key: 0,piece: 100,amount:200,sum: 300},{key: 1,piece: 1,amount:2,,sum: 2}]

---