Set

A Set object can be used to hold unique values (no repetitions are allowed). A value in a set can be anything (objects and primitive values).

The syntax new Set([iterable]) creates a Set object where iterable is an array or any other iterable object of values.

The size property returns the number of distinct values in a set.

For example:

let set = new Set([1, 2, 4, 2, 59, 9, 4, 9, 1]);
console.log(set.size); // 5

Methods:

add(value) Adds a new element with the given value to the Set.
delete(value) Deletes a specified value from the set.
has(value) Returns true if a specified value exists in the set and false otherwise.
clear() Clears the set.
values() Returns an Iterator of values in the set.

For example:

let set = new Set();

set.add(5).add(9).add(59).add(9);
console.log(set.has(9));

for (let v of set.values()) {
  console.log(v);
}

Set supports different data types i.e. 1 and "1" are two different values. NaN and undefined can also be stored in Set.

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