Traversable.sequences.js

var cloneObj = obj => {
    var newObj = {};
    Object.keys(obj).forEach((key) => {
        newObj[key] = obj[key];
    });
    return newObj;
};

var appendTrace = (trace, key, val) => {
    var newTrace = cloneObj(trace);
    newTrace[key] = val;

    return newTrace;
};

var variateFab = obj => {
    var keys = Object.keys(obj);
    var l = keys.length;
    var variate = (keyIndex, trace) => {
        if (keyIndex >= l) return trace;
        return obj[keys[keyIndex]].reduce((items, val) => {
            return items.concat(variate(keyIndex + 1, appendTrace(trace, keys[keyIndex], val)));
        }, []);
    };
    return variate;
};

function combinations(obj) {
    return variateFab(obj)(0, {});
}

combinations({
    color: ['red', 'green', 'blue'],
    size: ['xl', 'm'],
    lang: ['ru', 'ua', 'by', 'tr']
});

/*
[
    {color: 'red', size: 'xl', lang: 'ru'},
    {color: 'red', size: 'xl', lang: 'ua'},
    {color: 'red', size: 'xl', lang: 'by'},
    {color: 'red', size: 'xl', lang: 'tr'},
    {color: 'red', size: 'm',  lang: 'ru'},
    ...
]
*/