JS Built-ins
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ObjectObject.setPrototypeOfintermediate

Object.setPrototypeOf() — set to null

📖 Usage Example
// Set the prototype of an object
const animal = { breathe() { return true } }
const dog = {}
Object.setPrototypeOf(dog, animal)
dog.breathe()   // → true

Use Object.setPrototypeOf() to dynamically change an object's prototype, though creating objects with the correct prototype upfront is preferred.

Object.setPrototypeOf() — null prototype

Setting the prototype to null creates an object with no prototype chain — similar to Object.create(null). Such objects have no inherited methods.

Challenge: Set an object's prototype to null and verify it loses inherited methods.

💡 Hints (1)
  • • null prototype objects are useful as pure hash maps with no inherited methods