Automatically create object if undefined

Question

Is there an easy way to automatically add properties to objects if they don\'t allready exist?

Consider the following example:

var test = {}
test.hel         


        

Answer 1

let test = {};
test = {...test, hello: {...test.hello, world: 'Hello does exist!'}};
console.log(test);

When using the spread operator, the value can be undefined, it'll automatically create an object.