CONCEPTS
01Template literals
02Destructuring assignments
03Rest and Spread operators
04Optional chaining (?.) and Nullish coalescing (??)
05Symbols and Iterators
06Set and Map
SYNTAX_DEMO
Modernizing code
// Optional Chaining & Nullish Coalescing
const user = { profile: { name: "Alice" } };
const userAge = user.profile?.age ?? 18;
// Map & Set
const uniqueIds = new Set([1, 1, 2, 3]);
uniqueIds.add(4);
const cache = new Map();
cache.set("key1", "data");
// Template Literals
console.log(`User age defaults to: ${userAge}`);