MiscJSDoc.ts 4.57 KB
/*
 * This file and its definitions are needed just so that ESDoc sees these
 * JSDoc documentation comments. Originally they were meant for some TypeScript
 * interfaces, but TypeScript strips away JSDoc comments near interfaces. Hence,
 * we need these bogus classes, which are not stripped away. This file on the
 * other hand, is not included in the release bundle.
 */
import { Subscriber } from './Subscriber';
import { TeardownLogic } from './Subscription';
import { Observable } from './Observable';
import './scheduler/MiscJSDoc';
import './observable/dom/MiscJSDoc';

/**
 * We need this JSDoc comment for affecting ESDoc.
 * @extends {Ignored}
 * @hide true
 */
export class ObservableDoc {
  /**
   * Creates a new Observable that will execute the specified function when a
   * {@link Subscriber} subscribes to it.
   *
   * <span class="informal">Creates an Observable with custom logic given in
   * the `subscribe` function.</span>
   *
   * <img src="./img/create.png" width="100%">
   *
   * `create` converts a `subscribe` function to an actual Observable. This is
   * equivalent to calling the Observable constructor. Write the `subscribe`
   * function so that it behaves as an Observable: It should invoke the
   * Subscriber's `next`, `error`, and `complete` methods following the
   * *Observable Contract*. A well-formed Observable must invoke either the
   * Subscriber's `complete` method exactly once or its `error` method exactly
   * once, and invoke nothing else thereafter.
   *
   * Most of the times you should not need to use `create` because existing
   * creation operators (together with instance combination operators) allow you
   * to create an Observable for most of the use cases. However, `create` is
   * low-level and is able to create any Observable.
   *
   * @example <caption>Emit three random numbers, then complete.</caption>
   * var result = Rx.Observable.create(function (subscriber) {
   *   subscriber.next(Math.random());
   *   subscriber.next(Math.random());
   *   subscriber.next(Math.random());
   *   subscriber.complete();
   * });
   * result.subscribe(x => console.log(x));
   *
   * @see {@link empty}
   * @see {@link never}
   * @see {@link of}
   * @see {@link throw}
   *
   * @param {function(subscriber: Subscriber): TeardownLogic} [subscribe] A
   * function that accepts a {@link Subscriber}, and invokes its `next`,
   * `error`, and `complete` methods as appropriate, and should return some
   * logic for tear down, either as a {@link Subscription} or as a function.
   * @return {Observable} An Observable that, when subscribed, will execute the
   * specified function.
   * @static true
   * @name create
   * @owner Observable
   */
  static create<T>(subscribe?: <R>(subscriber: Subscriber<R>) => TeardownLogic): Observable<T> {
    return new Observable<T>(subscribe);
  };
}

/**
 * An interface for a consumer of push-based notifications delivered by an
 * {@link Observable}.
 *
 * ```ts
 * interface Observer<T> {
 *   closed?: boolean;
 *   next: (value: T) => void;
 *   error: (err: any) => void;
 *   complete: () => void;
 * }
 * ```
 *
 * An object conforming to the Observer interface is usually
 * given to the `observable.subscribe(observer)` method, and the Observable will
 * call the Observer's `next(value)` method to provide notifications. A
 * well-behaved Observable will call an Observer's `complete()` method exactly
 * once or the Observer's `error(err)` method exactly once, as the last
 * notification delivered.
 *
 * @interface
 * @name Observer
 * @noimport true
 */
export class ObserverDoc<T> {
  /**
   * An optional flag to indicate whether this Observer, when used as a
   * subscriber, has already been unsubscribed from its Observable.
   * @type {boolean}
   */
  closed: boolean = false;
  /**
   * The callback to receive notifications of type `next` from the Observable,
   * with a value. The Observable may call this method 0 or more times.
   * @param {T} value The `next` value.
   * @return {void}
   */
  next(value: T): void {
    return void 0;
  }
  /**
   * The callback to receive notifications of type `error` from the Observable,
   * with an attached {@link Error}. Notifies the Observer that the Observable
   * has experienced an error condition.
   * @param {any} err The `error` exception.
   * @return {void}
   */
  error(err: any): void {
    return void 0;
  }
  /**
   * The callback to receive a valueless notification of type `complete` from
   * the Observable. Notifies the Observer that the Observable has finished
   * sending push-based notifications.
   * @return {void}
   */
  complete(): void {
    return void 0;
  }
}