function _skipFirstGeneratorNext(fn) { return function () { var it = fn.apply(this, arguments); it.next(); return it; }; } function _awaitAsyncGenerator(value) { return new _AwaitValue(value); } function _wrapAsyncGenerator(fn) { return function () { return new _AsyncGenerator(fn.apply(this, arguments)); }; } function _AsyncGenerator(gen) { var front, back; function send(key, arg) { return new Promise(function (resolve, reject) { var request = { key: key, arg: arg, resolve: resolve, reject: reject, next: null }; if (back) { back = back.next = request; } else { front = back = request; resume(key, arg); } }); } function resume(key, arg) { try { var result = gen[key](arg); var value = result.value; var wrappedAwait = value instanceof _AwaitValue; Promise.resolve(wrappedAwait ? value.wrapped : value).then(function (arg) { if (wrappedAwait) { resume(key === "return" ? "return" : "next", arg); return; } settle(result.done ? "return" : "normal", arg); }, function (err) { resume("throw", err); }); } catch (err) { settle("throw", err); } } function settle(type, value) { switch (type) { case "return": front.resolve({ value: value, done: true }); break; case "throw": front.reject(value); break; default: front.resolve({ value: value, done: false }); break; } front = front.next; if (front) { resume(front.key, front.arg); } else { back = null; } } this._invoke = send; if (typeof gen.return !== "function") { this.return = undefined; } } if (typeof Symbol === "function" && Symbol.asyncIterator) { _AsyncGenerator.prototype[Symbol.asyncIterator] = function () { return this; }; } _AsyncGenerator.prototype.next = function (arg) { return this._invoke("next", arg); }; _AsyncGenerator.prototype.throw = function (arg) { return this._invoke("throw", arg); }; _AsyncGenerator.prototype.return = function (arg) { return this._invoke("return", arg); }; function _AwaitValue(value) { this.wrapped = value; } function foo() { return _foo.apply(this, arguments); } function _foo() { _foo = _wrapAsyncGenerator(_skipFirstGeneratorNext(function* () { let _functionSent = yield; _functionSent = yield _awaitAsyncGenerator(_functionSent); })); return _foo.apply(this, arguments); }