Understanding the 'Set' Object in ES6

JavaScript ES6, also known as ECMAScript 2015, introduced a new data object called 'Set'. The Set object is a collection of unique values. It can store values of any type, including primitive and object references.

The primary reason for using a Set over a standard Array is that Set only allows unique values, no duplicate values are allowed. This can be very useful when you need to ensure that an element only occurs once in a collection.

Practical Examples of 'Set' in ES6

Let's consider a practical example. Suppose you want to remove duplicate values from an array. You can make use of the Set object.

const array = [1, 2, 2, 3, 4, 4, 5, 5];
const uniqueArray = [...new Set(array)];
console.log(uniqueArray); // Output: [1, 2, 3, 4, 5]

In this example, we are creating a Set from the array, which automatically removes all the duplicates because a Set only allows unique values. Then, we are using the spread operator (...) to create a new array from the unique values in the Set.

Additional Insights and Best Practices

While the 'Set' object can be incredibly useful, it's essential to remember that it's not always the best tool for every job. If you need to store key-value pairs, you might be better off using a Map object, which is also introduced in ES6.

And, if you need to store an ordered list of values, where the position of the element is essential, the good old Array might still be your best bet.

Finally, because the 'Set' object is only available in ES6 and later, make sure to check if the 'Set' object is supported in your target environment before using it in your code.