JavaScript ES6新特性

Map和Set

'use strict';

let map = new Map([['a', 1], ['b', 2]]);
console.log(map.get('a'));
map.set('c', 3);
console.log(map);
console.log(map.get('a') + 100);
map.delete('a');
console.log(map);
console.log('------');

let set = new Set([1,2,3,3,3]);
console.log(set);
set.add(4);
set.delete(3)
let flag = set.has(2);
console.log(flag);