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Chapter XXI · The `this` Keyword

Explicit Binding

Explicit binding allows developers to manually assign a specific `this` context using `call`, `apply`, or `bind`.

01 How It Works

Think of handing a specific ID badge directly to a worker before they step onto the floor.

Methods like `call` and `apply` invoke functions immediately with a forced `this` target, while `bind` returns a permanently locked wrapper function.

example.js
function greet() {
  console.log(this.name);
}
const user = { name: "Alice" };
greet.call(user); // "Alice"

  1. 1. Target a function with an ambiguous `this` context.

  2. 2. Use `.call()`, `.apply()`, or `.bind()` to supply an explicit object.

  3. 3. Execute function with guaranteed context binding.

02 Practical Example

Here is how you might see this concept applied in real-world code:

practical.js
function show() { console.log(this.id); }
show.call({ id: 99 });

Key Takeaway

Explicit binding lets you manually control and override what `this` points to.

Related Concepts