How to flatten array in jQuery?

Question

How to simply flatten array in jQuery? I have:

[1, 2, [3, 4], [5, 6], 7]

And I want:

[1, 2, 3, 4, 5, 6, 7]

Answer 1

To recursively flatten an array you can use the native Array.reduce function. The is no need to use jQuery for that.

function flatten(arr) {
    return arr.reduce(function flatten(res, a) { 
        Array.isArray(a) ? a.reduce(flatten, res) : res.push(a);
        return res;
    }, []);
}

Executing

flatten([1, 2, [3, 4, [5, 6]]])

returns

[ 1, 2, 3, 4, 5, 6 ]