mergeDeep

const o1 = {
    "a": 1,
    "b": 2
}

const o2 = {
    "c": 3,
    "d": 4,
    "e": {
        f: 15
    }
}

const merged = fyzUtils.mergeDeep(o1, o2);

const merged1 = merged.a;
const merged2 = merged.e.f;