Q26. Explain the concept of this keyword in different contexts.

// ১. Global context
console.log(this); // window (ব্রাউজারে)

// ২. সাধারণ function — অ-কঠোর মোডে
function show() {
  console.log(this === window); // true
}
show();

// ৩. Method — this হলো সেই object
const user = {
  name: "Rahim",
  show() {
    console.log(this.name); // "Rahim"
  },
};
user.show();

const user = {
  name: "Rahim",
  show() {
    console.log(this.name);
  },
};

const fn = user.show;
fn(); // this আর user নয়

const user = {
  name: "Rahim",

  arrow: () => this.name, // ধার করা this

  regular: function () {
    return this.name;
  },

  method: function () {
    // ভেতরের arrow টেনে আনার পরেও this ঠিক থাকে
    const inner = () => this.name;
    return inner();
  },
};

console.log(user.method()); // "Rahim"

class User {
  constructor() {
    this.name = "Rahim";
  }

  show() {
    return this.name; // new করে ডাকলে ঠিক থাকে
  }
}

const show = new User().show;
// show(); // TypeError: this is undefined

function show() {
  console.log(this.name);
}

const user = { name: "Rahim", show };

show.call({ name: "Karim" }); // "Karim"
show.apply({ name: "Jamal" }); // "Jamal"

const bound = show.bind({ name: "Rahim" });
bound(); // "Rahim"