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- import { Subscriber } from '../Subscriber';
- /**
- * 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>
- *
- * <img src="./img/mapTo.png" width="100%">
- *
- * 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 <caption>Map every click to the string 'Hi'</caption>
- * var clicks = Rx.Observable.fromEvent(document, 'click');
- * var greetings = clicks.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(value) {
- return (source) => source.lift(new MapToOperator(value));
- }
- class MapToOperator {
- constructor(value) {
- this.value = value;
- }
- call(subscriber, source) {
- return source.subscribe(new MapToSubscriber(subscriber, this.value));
- }
- }
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- class MapToSubscriber extends Subscriber {
- constructor(destination, value) {
- super(destination);
- this.value = value;
- }
- _next(x) {
- this.destination.next(this.value);
- }
- }
- //# sourceMappingURL=mapTo.js.map
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