ES6 操做数组的并集／交集／差集

使用ES6 操做数组

let a = new Set([1, 2, 3]);
let b = new Set([3, 5, 2]); 

// 并集
let unionSet = new Set([...a, ...b]);
//[1,2,3,5]


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


// ab差集
let differenceABSet = new Set([...a].filter(x => !b.has(x)));