| import { Operator } from '../Operator'; |
| import { Observable } from '../Observable'; |
| import { Subscriber } from '../Subscriber'; |
| import { Observer, OperatorFunction } from '../types'; |
| |
| /** |
| * Returns an Observable that emits whether or not every item of the source satisfies the condition specified. |
| * |
| * ## Example |
| * A simple example emitting true if all elements are less than 5, false otherwise |
| * ```ts |
| * import { of } from 'rxjs'; |
| * import { every } from 'rxjs/operators'; |
| * |
| * of(1, 2, 3, 4, 5, 6).pipe( |
| * every(x => x < 5), |
| * ) |
| * .subscribe(x => console.log(x)); // -> false |
| * ``` |
| * |
| * @param {function} predicate A function for determining if an item meets a specified condition. |
| * @param {any} [thisArg] Optional object to use for `this` in the callback. |
| * @return {Observable} An Observable of booleans that determines if all items of the source Observable meet the condition specified. |
| * @method every |
| * @owner Observable |
| */ |
| export function every<T>(predicate: (value: T, index: number, source: Observable<T>) => boolean, |
| thisArg?: any): OperatorFunction<T, boolean> { |
| return (source: Observable<T>) => source.lift(new EveryOperator(predicate, thisArg, source)); |
| } |
| |
| class EveryOperator<T> implements Operator<T, boolean> { |
| constructor(private predicate: (value: T, index: number, source: Observable<T>) => boolean, |
| private thisArg?: any, |
| private source?: Observable<T>) { |
| } |
| |
| call(observer: Subscriber<boolean>, source: any): any { |
| return source.subscribe(new EverySubscriber(observer, this.predicate, this.thisArg, this.source)); |
| } |
| } |
| |
| /** |
| * We need this JSDoc comment for affecting ESDoc. |
| * @ignore |
| * @extends {Ignored} |
| */ |
| class EverySubscriber<T> extends Subscriber<T> { |
| private index: number = 0; |
| |
| constructor(destination: Observer<boolean>, |
| private predicate: (value: T, index: number, source: Observable<T>) => boolean, |
| private thisArg: any, |
| private source?: Observable<T>) { |
| super(destination); |
| this.thisArg = thisArg || this; |
| } |
| |
| private notifyComplete(everyValueMatch: boolean): void { |
| this.destination.next(everyValueMatch); |
| this.destination.complete(); |
| } |
| |
| protected _next(value: T): void { |
| let result = false; |
| try { |
| result = this.predicate.call(this.thisArg, value, this.index++, this.source); |
| } catch (err) { |
| this.destination.error(err); |
| return; |
| } |
| |
| if (!result) { |
| this.notifyComplete(false); |
| } |
| } |
| |
| protected _complete(): void { |
| this.notifyComplete(true); |
| } |
| } |