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- import { Falsy, MonoTypeOperatorFunction, OperatorFunction } from '../types';
- import { operate } from '../util/lift';
- import { createOperatorSubscriber } from './OperatorSubscriber';
- export function skipWhile<T>(predicate: BooleanConstructor): OperatorFunction<T, Extract<T, Falsy> extends never ? never : T>;
- export function skipWhile<T>(predicate: (value: T, index: number) => true): OperatorFunction<T, never>;
- export function skipWhile<T>(predicate: (value: T, index: number) => boolean): MonoTypeOperatorFunction<T>;
- /**
- * Returns an Observable that skips all items emitted by the source Observable as long as a specified condition holds
- * true, but emits all further source items as soon as the condition becomes false.
- *
- * 
- *
- * Skips all the notifications with a truthy predicate. It will not skip the notifications when the predicate is falsy.
- * It can also be skipped using index. Once the predicate is true, it will not be called again.
- *
- * ## Example
- *
- * Skip some super heroes
- *
- * ```ts
- * import { from, skipWhile } from 'rxjs';
- *
- * const source = from(['Green Arrow', 'SuperMan', 'Flash', 'SuperGirl', 'Black Canary'])
- * // Skip the heroes until SuperGirl
- * const example = source.pipe(skipWhile(hero => hero !== 'SuperGirl'));
- * // output: SuperGirl, Black Canary
- * example.subscribe(femaleHero => console.log(femaleHero));
- * ```
- *
- * Skip values from the array until index 5
- *
- * ```ts
- * import { from, skipWhile } from 'rxjs';
- *
- * const source = from([1, 2, 3, 4, 5, 6, 7, 9, 10]);
- * const example = source.pipe(skipWhile((_, i) => i !== 5));
- * // output: 6, 7, 9, 10
- * example.subscribe(value => console.log(value));
- * ```
- *
- * @see {@link last}
- * @see {@link skip}
- * @see {@link skipUntil}
- * @see {@link skipLast}
- *
- * @param predicate A function to test each item emitted from the source Observable.
- * @return A function that returns an Observable that begins emitting items
- * emitted by the source Observable when the specified predicate becomes false.
- */
- export function skipWhile<T>(predicate: (value: T, index: number) => boolean): MonoTypeOperatorFunction<T> {
- return operate((source, subscriber) => {
- let taking = false;
- let index = 0;
- source.subscribe(
- createOperatorSubscriber(subscriber, (value) => (taking || (taking = !predicate(value, index++))) && subscriber.next(value))
- );
- });
- }
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