| 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 declare function mapTo<T, R>(value: R): OperatorFunction<T, R>; |