Transform an Object to an ES6 Map

objectToMap.js

function objectToMap(obj){
    let map = new Map();
    let i;
    let keys = Object.keys(obj);
    let length = keys.length;
    
    for (i = 0; i < length; ++i){
        let temp = obj[keys[i]];
        if (temp instanceof Object){
            map.set(keys[i], objectToMap(temp));
        } else {
            map.set(keys[i], temp);
        }
    }
    return map;
}