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@reactivex/rxjs

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Reactive Extensions for modern JavaScript

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import { Observable } from '../Observable'; import { Operator } from '../Operator'; import { Subscriber } from '../Subscriber'; /** * Emits only the first value emitted by the source Observable that meets some * condition. * * <span class="informal">Finds the first value that passes some test and emits * that.</span> * * <img src="./img/find.png" width="100%"> * * `find` searches for the first item in the source Observable that matches the * specified condition embodied by the `predicate`, and returns the first * occurrence in the source. Unlike {@link first}, the `predicate` is required * in `find`, and does not emit an error if a valid value is not found. * * @example <caption>Find and emit the first click that happens on a DIV element</caption> * var clicks = Rx.Observable.fromEvent(document, 'click'); * var result = clicks.find(ev => ev.target.tagName === 'DIV'); * result.subscribe(x => console.log(x)); * * @see {@link filter} * @see {@link first} * @see {@link findIndex} * @see {@link take} * * @param {function(value: T, index: number, source: Observable<T>): boolean} predicate * A function called with each item to test for condition matching. * @param {any} [thisArg] An optional argument to determine the value of `this` * in the `predicate` function. * @return {Observable<T>} An Observable of the first item that matches the * condition. * @method find * @owner Observable */ export declare function find<T>(predicate: (value: T, index: number, source: Observable<T>) => boolean, thisArg?: any): Observable<T>; export interface FindSignature<T> { (predicate: (value: T, index: number, source: Observable<T>) => boolean, thisArg?: any): Observable<T>; } export declare class FindValueOperator<T> implements Operator<T, T> { private predicate; private source; private yieldIndex; private thisArg; constructor(predicate: (value: T, index: number, source: Observable<T>) => boolean, source: Observable<T>, yieldIndex: boolean, thisArg?: any); call(observer: Subscriber<T>, source: any): any; } /** * We need this JSDoc comment for affecting ESDoc. * @ignore * @extends {Ignored} */ export declare class FindValueSubscriber<T> extends Subscriber<T> { private predicate; private source; private yieldIndex; private thisArg; private index; constructor(destination: Subscriber<T>, predicate: (value: T, index: number, source: Observable<T>) => boolean, source: Observable<T>, yieldIndex: boolean, thisArg?: any); private notifyComplete(value); protected _next(value: T): void; protected _complete(): void; }