Make arrays and functions flat.

flatArraysAndFunctions.js

var some = function (x) {
    if (Array.isArray(x)) {
        return [].concat.apply([], x.map(some));
    }
    if (typeof x === "function") {
        return some(x());
    }
    return x;
};

some([function () {
    return [1];
}, 2, [3], function () {
    return 4;
}, [5, [6]]]); // [1, 2, 3, 4, 5, 6]