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- import { ArrayObservable } from '../observable/ArrayObservable';
- import { ScalarObservable } from '../observable/ScalarObservable';
- import { EmptyObservable } from '../observable/EmptyObservable';
- import { concat as concatStatic } from '../observable/concat';
- import { isScheduler } from '../util/isScheduler';
- /* tslint:enable:max-line-length */
- /**
- * Returns an Observable that emits the items you specify as arguments before it begins to emit
- * items emitted by the source Observable.
- *
- * <img src="./img/startWith.png" width="100%">
- *
- * @param {...T} values - Items you want the modified Observable to emit first.
- * @param {Scheduler} [scheduler] - A {@link IScheduler} to use for scheduling
- * the emissions of the `next` notifications.
- * @return {Observable} An Observable that emits the items in the specified Iterable and then emits the items
- * emitted by the source Observable.
- * @method startWith
- * @owner Observable
- */
- export function startWith(...array) {
- return (source) => {
- let scheduler = array[array.length - 1];
- if (isScheduler(scheduler)) {
- array.pop();
- }
- else {
- scheduler = null;
- }
- const len = array.length;
- if (len === 1) {
- return concatStatic(new ScalarObservable(array[0], scheduler), source);
- }
- else if (len > 1) {
- return concatStatic(new ArrayObservable(array, scheduler), source);
- }
- else {
- return concatStatic(new EmptyObservable(scheduler), source);
- }
- };
- }
- //# sourceMappingURL=startWith.js.map
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