hash of promises

hash.ts

export function hash(o: Object): Promise<any> {
    var keys = Object.keys(o);
    var promises = keys.map(key => Promise.resolve(o[key]));
    return Promise.all(promises).then(function (values) {
        return keys.reduce(function (hash, key, i) {
            hash[key] = values[i];
            return hash;
        }, {});
    });
}