(2)ES6解构赋值-数组篇

1.解构赋值-数组篇 //Destrcturing(解构)
//ES5
/*
var a = 1;
var b = 2;
var c = 3;
*/
//ES6
var [a,b,c] = [1,2,3];
console.log(b);

//demo2
let [
foo,
[
[bar],
base
]
] = [
1,
[
[2],
3
]
];

console.log(bar);//2
console.log(base);//3

//demo3
let [,a,] = [1,2,3];
console.log(a);//2

//demo4
let [zero,...j] = [0,1,2,3,4]; //注意是三个.
console.log(j); //[1,2,3,4]
//demo5
let [a,b] = [1];
console.log(a); //1
console.log(b); //undefined

//demo6 不完全解构
let[a,[b],c] = [1,[2,3],4];
console.log(b); //2
console.log(c);//4

//demo7 制定默认值
var [temp = 'jewave'] = [];
console.log(temp);//'jewave'

// var [temp='jewave'] = ['xiang'];
// var [p,q = 'aaa'] = ['bbb',undefined] 【'bbb','aaa'】
// var [temp] = 1; Iterator接口之非遍历结构报错 var [temp]= undefined;报错

//demo8  Iterator接口之可遍历结构

let [a,b,c] = new Set(['x','y','z']);

console.log(b); // 'y'

 

function*  fibs() {//指针函数

　　let a = 0;

　　let b = 1;

　　while (true) {

　　　　yield a;

　　　　[a,b] = [b,a+b];

　　}

};

var [fir,sec,thi,fou,fif,six] = fibs();

console.log(six); //5