+++ /dev/null
-import { Operator } from '../Operator';
-import { Subscriber } from '../Subscriber';
-import { Observable } from '../Observable';
-import { OperatorFunction } from '../types';
-
-/**
- * Emits the given constant value on the output Observable every time the source
- * Observable emits a value.
- *
- * <span class="informal">Like {@link map}, but it maps every source value to
- * the same output value every time.</span>
- *
- * ![](mapTo.png)
- *
- * Takes a constant `value` as argument, and emits that whenever the source
- * Observable emits a value. In other words, ignores the actual source value,
- * and simply uses the emission moment to know when to emit the given `value`.
- *
- * ## Example
- * Map every click to the string 'Hi'
- * ```ts
- * import { fromEvent } from 'rxjs';
- * import { mapTo } from 'rxjs/operators';
- *
- * const clicks = fromEvent(document, 'click');
- * const greetings = clicks.pipe(mapTo('Hi'));
- * greetings.subscribe(x => console.log(x));
- * ```
- *
- * @see {@link map}
- *
- * @param {any} value The value to map each source value to.
- * @return {Observable} An Observable that emits the given `value` every time
- * the source Observable emits something.
- * @method mapTo
- * @owner Observable
- */
-export function mapTo<T, R>(value: R): OperatorFunction<T, R> {
- return (source: Observable<T>) => source.lift(new MapToOperator(value));
-}
-
-class MapToOperator<T, R> implements Operator<T, R> {
-
- value: R;
-
- constructor(value: R) {
- this.value = value;
- }
-
- call(subscriber: Subscriber<R>, source: any): any {
- return source.subscribe(new MapToSubscriber(subscriber, this.value));
- }
-}
-
-/**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
-class MapToSubscriber<T, R> extends Subscriber<T> {
-
- value: R;
-
- constructor(destination: Subscriber<R>, value: R) {
- super(destination);
- this.value = value;
- }
-
- protected _next(x: T) {
- this.destination.next(this.value);
- }
-}