Rest Parameters let x = 10, y = 20, z = 30; function max(array) { return Math.max.apply(null, array); } max([x, y, z]); // => 30 function max(...array) { return Math.max.apply(null, array); } max(x, y, z); // => 30 ES6 ES6
let hundred = 100; let multiple = function (x, y) { return x * y; } console.log(`hundred is ${number}`); // => hundred is 100 console.log(`hundred * 10 is ${multiple(number, 10)}`); // => hundred * 10 is 1000 Template Strings ES6
Set WeakSet var set1 = new Set([1, 2, 2, 3, 3, 3, 4, 4, 4, 4]); // => [1, 2, 3, 4] var set2 = new Set(set1); var set3 = new Set(set1.entries()); var set4 = new Set(set1.keys()); ES6
Map WeakMap var arrayKey = []; var map = new Map(); map.set(1, 'This is a value'); map.set(arrayKey, 'This is also value'); map.get(1); // This is a value map.get(arrayKey); // This is also value ES6