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. * * * * @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