JS Map Function

So this one really isn't new. However, it was pretty new to me as I never had used it until I started working with Gatsby and React.

The map function is a way to loop through an array. However, it allows you to do some different things and is a simpler syntax in a lot of ways. Take the code below for example:

let myArray = [9,5,7,2];
let doubleArray = myArray.map((val, i, arr) => {
  return val * 2;
});

After this myArray would stay the same, however, doubleArray would look like:

[18,10,14,4]

You can also omit the return statement and just perform some action on each element of the array.