tts.DeferredPromise = function() {
    var _resolve = null;
    var _reject = null;

    this.promise = new Promise(function(resolve, reject) {
        _resolve = resolve;
        _reject = reject;
    });
    this.then = function() {
        return this.promise.then(...arguments);
    }
    this.catch = function() {
        return this.promise.catch(...arguments);
    }
    this.resolve = function() {
        _resolve(...arguments);
    }
    this.reject = function() {
        _reject(...arguments);
    }
};