1、Destructuring
ES6允许按照一定模式，从数组和对象中提取值，对变量进行赋值，这称为“解构”。
2、不完全解构
等号左边的模式，只匹配一部分的等号右边的数组。
3、指定默认值
注意：ES6内部使用严格相等运算符（===）判断一个位置是否有值。所以，如果一个数组成员不严格等于undefined，默认值是不会生效的。
4、let和const命令
只要某种数据结构具有lterator接口，都可以采用数组形式的结构赋值。
（1）数组解构
<script type="text/traceur"> //ES5 //var a =1; //var b=2; //var c=3; //ES6 var [a,b,c] = [1,2,3]; console.log(a); console.log(b); console.log(c); </script> 结果：1
2
3
（2）对应位置
let [foo,[[bar],base]] = [1,[[2],3]]; console.log(foo); //1; console.log(bar); //2 console.log(base); //3 let[, , third] = ["first",'second","third"]; console.log(third); //third let[one, ,three] = ["One","Two","Three"]; console.log(one); //One console.log(three); //Three let [head,...tail] = [0,1,2,3,4,5,6,7,8,9]; console.log(head); //0 console.log(tail); //[1,2,3,4,5,6,7,8,9] （3）不完全解构
<script type="text/traceur"> let [x,y] = [1,2,3]; console.log(x); //1 console.log(y); //2 let [a,[b],c] = [1,[2,3],4]; console.log(a); //1 console.log(b); //2/[2,3] console.log(c); //4 </script>
（4）指定默认值
<script type="text/traceur"> var [temp = "string"] = []; console.log(temp); //string var [temp = "string"] = ["tempString"]; console.log(temp); //tempString var [x="aaa",y] = ["bbb"]; console.log(x); //bbb console.log(y); //undefined var [m,n="aaa"] = ["bbb"]; console.log(m); //bbb console.log(n); //aaa var [p,q="aaa"] = ["bbb",undefined]; console.log(p); //bbb console.log(q); //aaa </script> 解析：从上述案例可以看出，若只赋值了一个，即会覆盖之前的值；若之前未定义，则会显示“undefined”；若之前变量有值，强行赋值了undefined，则并不会产生什么影响。
（5）非遍历结构——报错
<script type="text/traceur"> var [temp1] = 1; //1 is not a function at eval var [temp2] =false; //false is not a function at eval var [temp3] =NaN; var [temp4] = undefined; //Cannot read var [temp5] =null; </script>
（6）let和const命令——Iterator接口
<script type="text/traceur"> let [a,b,c] = new Set(["a","b","c"]); console.log(a); //a console.log(b); //b console.log(c); //c //由于它是可遍历的，所以会显示出来； function* fibs(){ //指针类型 let a=0; let b=1; while(true){ yield a; [a,b] = [b,a+b]; } }; var [first,second,third,fourth,fifth,sixth] = fibs(); console.log(sixth); //5 </script> 解析：在上述代码中，函数fibs()可对指针进行索引，对于下标的值，所对应的即为数组形式下的解构赋值，实现数组赋值解构化。
