Arrays

There are some new properties added to the global Array object and to its instances to make working with arrays easier. Arrays in JavaScript lacked features and capabilities when compared with programming languages such as Python and Ruby. Let's take a look at some popular methods associated with arrays and their use cases.

The Array.from(iterable, mapFunc, this) method

The Array.from() method creates a new array instance from an iterable object. The first argument is a reference to the iterable object. The second argument is optional and is a callback (known as the Map function) that is called for every element of the iterable object. The third argument is also optional and is the value of this inside the Map function.

Here is an example to demonstrate this:

let str = "0123";
let arr = Array.from(str, value => parseInt(value) * 5);
console.log(arr);

The output is:

[0, 5, 10, 15].

Array.from would be extremely useful in converting an "array-like" structure to the actual array. For example...