//数组的各种情况解构,按位置顺序来取
let [x,y,z]=[1,2,3];
console.log(x,y,z);

let [a1,[b1,c1]]=[10,[12,14]];
console.log(a1,b1,c1);

let [,,nice]=['YES','NO','PASS'];
console.log(nice);

let [p1,,p3]=[3,6,9];
console.log(p1,p3);

//...end表示后面所有参数,begin表达1
let [begin,...end]=[1,2,3,4,5,6,7,8,9,10];
console.log(begin);
console.log('=============');
console.log(end);

//y1会是undefined ,z1会是空数组
let [x1,y1,...z1]=['a'];
console.log(x1,y1,z1);

let [xxxx] = [];
let [xxx,yyy]=[1];
console.log(xxxx,yyy);

let [j,k]=[7,8,9];
console.log(j,k);

let [L1,[L3],L4]=[1,[2,3],4];
console.log(L1,L3,L4);

//下面会报错,只能赋值数组
//let [pp1]=1;
//let [pp2]=true;
// let [pp3]=NaN;
// let [pp4]=undefined;
// let [pp5]=null;
// let [pp6]={};

// @ts-ignore
let [q1,q2,q3]=new Set(['aaa','bbb','ccc']);
console.log(q1,q2,q3);

//生成器
function* fibs(){
    let a=0;
    let b=1;
    while (true){
        yield a;
        [a,b]=[b,a+b];//返回前个数字加上后个数字的队列如 0 1 1 2 3 5 8
    }
}

let [m1,m2,m3,m4,m5,m6] = fibs();//从生成器中取6次
console.log(m1,m2,m3,m4,m5,m6);

//生成器
function* test(){
    let x=0;
    while (true){
        yield x;
        x +=2;//返回第次加2
    }
}

let [cx1,cx2,cx3]=test();//从生成器中取3次
console.log(cx1,cx2,cx3);//- 0 2 4

//解构默认值
let [posX=0,posY=0]=[];
console.log(posX,posY);

let [meta1,meta2='a']=['b'];
console.log(meta1,meta2);

let [meta3,meta4='xxx']=['yyy',undefined];
console.log(meta3,meta4);

//undefined情况下默认值生效
let [defval=1]=[undefined];
console.log(defval);
//null情况下默认值无效
let [defval2=1]=[null];
console.log(defval2);


function f(){
    console.log('aaa');
}

let [zzz=f()]=[1];
console.log(zzz);
let [zzz1=f()]=[undefined];//函数没返回的话取undefined
console.log(zzz1);

//对象的解构,按对象属性名来取,与位置无关
let {name,age,address}={name:'RemoteDev',age:18,address:'中国上海'};
console.log(name,age,address);
let {age1,name1,address1}={name1:'RemoteDev',age1:18,address1:'中国上海'};
console.log(name1,age1,address1);
let {age2,name2,NewAddress}={name2:'RemoteDev',age2:18,address2:'中国上海'};
console.log(name2,age2,NewAddress);//会取不到NewAddress因为与对象名不同,NewAddress返回undefined

//通过别名的形式来取
let {age3,name3,address3: NewAddress2}={name3:'RemoteDev',age3:18,address3:'中国上海'};
console.log(name3,age3,NewAddress2);//这样可正常取address3值并赋值给NewAddress2

console.log('完成用别名来取对象属性值');
let personData = {UserName:'RemoteDev',Age:18,Address:'中国上海'};
let {UserName:_n,Age:_a,Address:_d}=personData;
console.log(_n,_a,_d);
//console.log(UserName);  //UserName is not defined 因为UserName是用来匹配对象属性名的,取值放到变量_n中,使用别名,只能用别名变量

let tmpObj={
    p:[
        'Ada',
        {
            'cap':'Mix'
        }
    ]
}
//p用来匹配对象属性p,v1取Ada值,cap取Mix值
let {p:[v1,{cap}]}=tmpObj;
console.log(v1,cap);
//别名匹配
let {p:[r1,{cap:r2}]}=tmpObj;
console.log(r1,r2);

//取整个对象值p
let {p,p:[val1,{cap:val2}]}=tmpObj;
console.log(p,val1,val2);

//嵌套对象的匹配与取值
let node = {
    loc: {
        start:{
            line:2,
            column:10
        }
    }
}

let {loc,loc:{start},loc:{start:{line}}} = node;
console.log(loc);
console.log(start);
console.log(line);

let _Obj={};
let _Arr=[];
({propA:_Obj.propA,propB:_Arr[0]}={propA:890,propB:false});//要加上()不然会与变量名_Obj,_Arr冲突
console.log(_Obj,_Arr);

//对象解构默认值
let {theKinds=9988}={};
console.log(theKinds);

let {kind1,kind2=5}={kind1:9};
console.log(kind1,kind2);

let {play:pname='Mick'}={play:'Linux'};
console.log(pname);

let {play:{subName='Default'}}={play:{subName:undefined}};
console.log(subName);

let {PI=3.14159}={PI:null};//这里默认值不生效
console.log(PI);

let {_pa,_pb}={VLCA:100,VLCB:200};
console.log(_pa,_pb);//这里取不到值,因匹配属性名不成功

let moveAction= {actionType:'Out'};
console.log(moveAction.actionType);

let {log,sin,cos}=Math;

//对数组属性进行解构
let numArr=[1,2,3];
let {0:first,[numArr.length-1]:last}=numArr;
console.log(first,last);


//字符串解构
const [nx1,nx2,nx3]='ABC';
console.log(nx1,nx2,nx3);
//字符属性解构
let {length:len}='RemoteDev';
console.log(len);

let {toString:s}=123;
console.log(s);
let {toString:s1}=true;
console.log(s1);

//因为undefined和null无法转换为对象所以下两个表达式会报错
//let {proA:__X}=undefined;
//let {proB:__Y}=null;

//函数参数解构
function Add([x,y]){
    return x+y;
}
let result = Add([6,9]);
console.log(result);

[[1,2],[3,4]].map(([x,y])=> console.log(x+y));
//函数参数默认值
function funcDef({x=0,y=0}={}){
    console.log([x,y]);
    return [x,y];
}

funcDef();
funcDef({x:50});
funcDef({x:10,y:20});
funcDef({y:100});
funcDef({});

//变量值交换
let NumberA=10;
let NumberB=20;
[NumberA,NumberB]=[NumberB,NumberA];
console.log(NumberA,NumberB);

function f1() {
    return [5,10,15];
}

let [e1,e2,e3]=f1();
console.log(e1,e2,e3);

function getTestObj() {
    return {
        a:5*2,
        b:10*2,
        c:15*2
    }
}

let {a:ca1,b:ca2,c:ca3}=getTestObj();
console.log(ca1,ca2,ca3);

//数组参数有序
function f2([x,y,z]) {
    console.log(x,y,z);
}
f2([9,8,7]);

//对象参数无序
function f3({x=0,y=0,z=0}={}) {
    console.log(x,y,z);
}
f3({x:3,z:9,y:80});

//通过解构提取JSONovrn
let jsondata = {
    _id:200,
    _status:"Success",
    _data:[168,578]
};
let {_id,_status,_data:arr}=jsondata;
console.log(_id,_status,arr);

//构造Map
let myMap = new Map();
myMap.set(1,100);
myMap.set(2,"OK");
myMap.set(3,false);
myMap.set('UI','ZJY');
console.log(myMap);
//遍历Map
for (const [k,v] of myMap) {
    console.log(k,v);
}