How to find all subsets of a set in JavaScript? (Powerset of array)

Question

I need to get all possible subsets of an array.

Say I have this:

[1, 2, 3] 

How do I get this?

[], [1], [2], [3], [1, 2], [2, 3], [1, 3], [1, 2, 3] 

I am interested in all subsets. For subsets of specific length, refer to the following questions:

• Finding subsets of size n: 1, 2
• Finding subsets of size > 1: 1

Answer 1

Here is one more very elegant solution with no loops or recursion, only using the map and reduce array native functions.

const getAllSubsets =         theArray => theArray.reduce(          (subsets, value) => subsets.concat(           subsets.map(set => [value,...set])          ),          [[]]        );    console.log(getAllSubsets([1,2,3]));