Let’s take the following list of names as an example. Janet
is a duplicate in there.
const list = [
'George',
'Janet',
'Emma',
'Eve',
'Charles',
'Janet',
'Tracey',
];
Using Set
, we can convert that array to a Set
object that stores unique values.
const unique = new Set(list);
As you can see, the duplicate Janet
is removed.
However, the Set
object is no array and thus usual array methods such as .forEach()
or .map()
won’t work. To fix this, you can convert the set back to an array by generating a new array based on the set using Array.from()
.
const unique = Array.from(new Set(list));
Of course, you can also use the spread operator.
const unique = [...new Set(list)];