JS Practice — Built-in Objects

Set size — after add

📖 Usage Example

const s = new Set([1, 2, 3])
console.log(s.size)   // → 3
s.add(4)
console.log(s.size)   // → 4

Read Set.size to get the number of unique values in the set.

Set.prototype.size

Adding a new value increases size by 1.

Challenge: Verify that size equals 1 after one add().

💡 Hints (1)