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