JS Practice — Built-in Objects

Set Constructor — deduplication

📖 Usage Example

const s1 = new Set()          // empty
const s2 = new Set([1, 2, 3]) // from array
console.log(s2.size) // → 3

Use the Set constructor to create a new set, optionally passing an iterable.

Set Constructor

Sets automatically deduplicate values. new Set([1,1,2]) has size 2.

Challenge: Verify that new Set([1,1,2]).size equals 2.

💡 Hints (1)