ES6 set 应用场景

1、数组去重

let arr = [3, 5, 2, 2, 5, 5];
let unique = [...new Set(arr)];
// [3, 5, 2]      

2、并集（Union）、交集（Intersect）和差集（Difference）

let a = new Set([1, 2, 3]);
let b = new Set([4, 3, 2]);

// 并集
let union = new Set([...a, ...b]);
// Set {1, 2, 3, 4}

// 交集
let intersect = new Set([...a].filter(x => b.has(x)));
// set {2, 3}

// 差集
let difference = new Set([...a].filter(x => !b.has(x)));
// Set {1}      

转载于:https://www.cnblogs.com/mengfangui/p/9580289.html