How to make a Set of 2-dimensional array unique

Let's assume that we are working with the following 2-dimensional array and we want to remove duplicates:

javascript
// [1,2] is a duplicated element
let array = [[1, 2], [2, 3], [2, 2], [4, 5], [1, 2]];

Wrong approach

If you try to create a unique set of elements:

javascript
let unique = new Set(array);

console.log(unique);
// Set(5) {[1, 2], [2, 3], [2, 2], [4, 5], [1, 2]}
// It doesn't work! We still have duplicates...

Right approach

Using a Set(array) object doesn't work in these cases. So, how we can do it?

javascript
// Defining an empty Set
let unique = new Set();

// Getting a no duplicates array
let noDuplicates = array.filter(elem => {
    
    // Array to string. [1,2] -> "[1,2]"
    let string = JSON.stringify(elem);
    
    // Is already in the Set
    let isAlreadySeen = unique.has(string);
    
    // Adding element to Set won't create duplicates
    unique.add(string);
    
    // Return result
    return isAlreadySeen ? false : true;
    
});

console.log(noDuplicates);
// [[1, 2], [2, 3], [2, 2], [4, 5]]