JS Practice — Built-in Objects

valueOf() — custom valueOf override

📖 Usage Example

// Retrieve the primitive value of an object
const n = new Number(42)
n.valueOf()   // → 42
const obj = { valueOf() { return 10 } }
obj + 5       // → 15

Use valueOf() to retrieve the underlying primitive value of an object; JavaScript calls it automatically in numeric contexts.

valueOf() — custom override

You can override valueOf() in your own objects to control how they convert to primitives, especially in arithmetic operations.

Challenge: Create an object with a custom valueOf() that returns a specific number.

💡 Hints (1)

• Override valueOf to control how an object converts to a primitive in arithmetic or comparisons