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Rakesh Reddy Peddamallu
Rakesh Reddy Peddamallu

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Javascript - Basics of using built-in Set method

#javascript

JavaScript Set - Concise Notes šŸš€

šŸ”¹ What is a Set?

A Set is a built-in JavaScript object that stores unique values (no duplicates).

šŸ”¹ Creating a Set 

const mySet = new Set([1, 2, 3, 4, 5]);
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šŸ”¹ Key Methods

Method Description Example Usage
.add(value) Adds a value to the Set mySet.add(6);
.delete(value) Removes a value mySet.delete(3);
.has(value) Checks if value exists mySet.has(2); // true
.clear() Removes all elements mySet.clear();
.size Returns the number of elements mySet.size; // 5

šŸ”¹ Iterating Over a Set 

mySet.forEach(value => console.log(value)); // Loop using forEach
for (let value of mySet) console.log(value); // Loop using for...of
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šŸ”¹ Convert Set to Array 

const numArray = [...mySet];
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šŸ”¹ Convert Array to Set (Remove Duplicates) 

const uniqueNums = new Set([1, 2, 2, 3, 4]); // {1, 2, 3, 4}
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šŸ”¹ When to Use a Set?

āœ… Fast lookups (O(1))

āœ… Removing duplicates

āœ… Tracking unique values

šŸš€ Best for performance when working with unique data!

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