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// 从数组和对象中提取值,赋值给变量,称为解构
// 数组解构 是有顺序的
// var arr = ["Jack", "Mark"];
// ES5中
// var name = arr[1]
// console.log(name); // Mark
// ES6中解构赋值
// let [, name] = arr;
// console.log(name); // Mark
let arr1 = [1, 2, [2.1, 2.2, 2.3, 2.4], 3, 4, 5, 6, 7];
// let [, , [a, b]] = arr1;
// console.log(a, b); // 2.1 2.2
// ...扩展运算符笼统的获取一些值组成数组 必须用在最后
// let [...a1, [a, b], ...a2] = arr1 // Rest element must be last element
// let [, , [a, b, ...a1], ...a2] = arr1;
// console.log(a, b, a1, a2); // 2.1 2.2 (2) [2.3, 2.4] (5) [3, 4, 5, 6, 7]
// 解构默认值
// let arr2 = [2];
// let [c = 1] = [2]; // 如果有值,就用解构的值,没有就读取默认值
// console.log(c); // 2
// let arr2 = [, 2];
// let [c = 1] = arr2;
// console.log(c); // 1
</script>
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