import { BaseObservableValue } from "./index";
export declare class FlatMapObservableValue<P, C> extends BaseObservableValue<C | undefined> {
    private readonly source;
    private readonly mapper;
    private sourceSubscription?;
    private targetSubscription?;
    constructor(source: BaseObservableValue<P>, mapper: (value: P) => (BaseObservableValue<C> | undefined));
    onUnsubscribeLast(): void;
    onSubscribeFirst(): void;
    private updateTargetSubscription;
    get(): C | undefined;
}
export declare function tests(): {
    "flatMap.get": (assert: any) => void;
    "flatMap update from source": (assert: any) => void;
    "flatMap update from target": (assert: any) => void;
};