Understanding the Spread Operator

The object spread syntax was recently added to the JavaScript specification.

Here are some reasons why it has become popular so quickly:

The spread operator lets you fully copy or do a "deep copy" of enumerable properties from one object to another object without having to perform a clone or copy operation with sometimes a couple of lines of JavaScript Code.

It's simplest use can be explained with a simple copy operation:

var c = {a:{b:1}, c:{arr: [a, b, c]}];
let d = {...c};

The advantage of using the object spread syntax becomes more apparent the more complex the objects that you are working with becomes.