How does prototypal inheritance work in JavaScript?

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Ravi Vishwakarma · Answer

In JavaScript, objects can inherit properties from other objects via the prototype chain. Each object has a prototype, and if a property is not found on the object itself, JavaScript will look up the prototype chain to find it.

Checking the Prototype Chain: You can check an object's prototype using:

Object.getPrototypeOf(obj): Returns the prototype of obj.
obj.__proto__: Accesses the prototype of obj (non-standard, should be avoided in favor of Object.getPrototypeOf).
instanceof: Checks if an object is an instance of a constructor function.

console.log(Object.getPrototypeOf(child) === parent); // true
console.log(child.__proto__ === parent); // true (non-standard way)
console.log(child instanceof Parent); // true (if using constructor function or class)

Prototypal inheritance provides a flexible and dynamic way to share properties and methods among objects in JavaScript, leveraging the prototype chain to enable reusability and efficient property lookup.

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How does prototypal inheritance work in JavaScript?

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