如何使用 RxJS 5 缓冲功能？

Question

我用谷歌搜索了很多，试图查看 d.ts 文件，但仍然无法理解问题所在。找不到 RxJs5 如何使用这个功能的例子。

var source = Observable.fromEvent(document.body, 'keypress');

    var delayedSource = source.delay(1000);

    var obs = source



      .buffer(() => {
        return   delayedSource;
      })

      .map((clickBuffer) => {
        return clickBuffer.length;
      });

我收到错误：

错误:(166, 15) TS2345: '() => Observable' 类型的参数不可分配给'Observable' 类型的参数。 类型“() => Observable”中缺少属性“_isScalar”。

buffer.d.ts 看起来是这样，我想我应该从中理解，但我不能。

import { Observable } from '../Observable';
/**
 * Buffers the incoming observable values until the passed `closingNotifier`
 * emits a value, at which point it emits the buffer on the returned observable
 * and starts a new buffer internally, awaiting the next time `closingNotifier`
 * emits.
 *
 * <img src="./img/buffer.png" width="100%">
 *
 * @param {Observable<any>} closingNotifier an Observable that signals the
 * buffer to be emitted} from the returned observable.
 * @returns {Observable<T[]>} an Observable of buffers, which are arrays of
 * values.
 */
export declare function buffer<T>(closingNotifier: Observable<any>): Observable<T[]>;
export interface BufferSignature<T> {
    (closingNotifier: Observable<any>): Observable<T[]>;
}

这个问题来自： Counting keypresses per second with angular 2 Rxjs

Answer 1

根据 Benjamin Gruenbaum 的评论，这解决了问题：

var source = Observable.fromEvent(document.body, 'keypress');

var delayedSource = source.delay(1000);

var obs = source

      .buffer(delayedSource)

      .map((clickBuffer) => {
        return clickBuffer.length;
      })