How would you remove the duplicate elements from this array?

const list = [
  { name: 'John' }, 
  { name: 'Sara' },
  { name: 'Sara' },
  { name: 'Lynn' },
  { name: 'Jake' }
];

There are a few ways to do this. Your first intuition might be to do something like this.

const uniqueList = Array.from(new Set(list))

It’s the right idea since creating a Set will ensure our collection only contains unique values and Array.from allows us to create a new, shallow-copied array. Unfortunately, Sets only enforce uniqueness for primitive values, but our list is full of objects.

Instead, we can do something like this.

const list = [
  { name: 'John' }, 
  { name: 'Sara' },
  { name: 'Sara' },
  { name: 'Lynn' },
  { name: 'Jake' }
];

const map = new Map();

list.forEach(item => {
	map.set(item.name, item)
});

const uniqueList = Array.from(map.values())

Notice we’re using a Map here. Since Map’s preserve insertion order, our uniqueList will have the same order as the original list, but without the duplicates since we’re using name as the key.