ECMAScript 2015 (ES6) aur Beyond: JavaScript Ka Revolution!

JavaScript mein 2015 ek kranti aayi thi — naam tha ES6 (ECMAScript 2015)! Iske baad se JavaScript ne har saal naye features dena shuru kiye. Chalo samjhein yeh “modern JS” kya hai aur aage kya aaya:

ES6: 5 Game-Changing Features

1. let aur const:

• var ki problems fix karne aaye (hoisting, scope issues).
• const se constants banaye:
  javascript const PI = 3.14; // Ab change nahi hoga! let count = 0; // Block-scoped variable

1. Arrow Functions (=>)

• Short syntax + this ki tension khatam:
  javascript // Purana tarika: function add(a, b) { return a + b; } // ES6: const add = (a, b) => a + b;

1. Classes

• OOP ko simple banaya:
  javascript class Dog { constructor(name) { this.name = name; } bark() { console.log('Bhow!'); } } const tommy = new Dog('Tommy');

1. Template Literals

• Dynamic strings aasaan hue:
  javascript const user = 'Amit'; console.log(`Hello ${user}!`); // Backticks (``) use karo

1. Destructuring

• Objects/Arrays se data nikalo seconds mein:
  javascript const [x, y] = [10, 20]; // x=10, y=20 const { name } = { name: 'Riya', age: 25 }; // name='Riya'

ES7/ES8: Next Level Features

ES9 to ES12: Sab Kuch Simple!

1. ES9: Spread Operator (...)

• Objects ko easily merge karo:
  javascript const obj1 = { a: 1 }; const obj2 = { ...obj1, b: 2 }; // {a:1, b:2}

1. ES10: flat() Arrays

• Nested arrays ko seedha karo:
  javascript [1, [2,3]].flat() // [1,2,3]

1. ES11: Nullish Coalescing (??)

• 0, '' ko bachate hue default values set karo:
  javascript const price = userInput ?? 100; // userInput=null/undefined ho toh 100

1. ES12: Logical Assignment

• Conditions ke saath assignment:
  javascript let x = 0; x ||= 5; // x=5 (if x falsy)

Kyon Important Hai ES6+?

1. Code Kam, Kaam Zyada:

• 10 lines ka code 2 lines mein!

1. Readability Badhao:

• async/await > Callback Hell 😇

1. Industry Standard:

• React/Vue/Angular sab ES6 use karte hain.

Kaise Seekhe ES6+?

1. Free Resources:

• ES6 Cheatsheet (PDF download karo)
• YouTube: Akshay Saini’s “Namaste JavaScript”

1. Practice Platforms:

• LeetCode (ES6 problems)
• CodePen (Live testing)

1. Babel:

• Purane browsers ko modern code samjhaane ka jadu!

   npm install @babel/core @babel/preset-env

Future: ECMAScript 2023 (ES14)

• findLast(): Array ke end se search karo.
• # Private Class Fields:

  class Wallet {
    #balance = 0; // Private! Bahar access nahi
  }

Final Tip: “Start Using ES6 Today!”

// Purana JS (Avoid!)
var name = 'Old';
function hello() { return 'Hi ' + name; }

// ES6 (Yeh karo!)
const name = 'Modern';
const hello = () => `Hi ${name}`; 

Browser Support?

• Chrome/Firefox/Edge: 95%+ features supported.
• Internet Explorer? Bhool jao! 🚫

Aaj se shuru karo:

1. let/const use karna.
2. Arrow functions try karo.
3. Ek class banao!
   Kal tak aapka code “zamaane se aage” hoga! 🔥