import { BaseSubContext } from "./context";
import { IRef, ISource, Params, SubFn, Subscription } from "./model";
export declare class Reference<V, P extends Params> extends BaseSubContext implements IRef<V>, ISource<V> {
    private pullValue;
    private args;
    name: string | undefined;
    onNoSubscribers: (() => void) | null;
    private lastValue;
    private subscribers;
    constructor(pullValue: SubFn<V, P>, args: P);
    deref(): V;
    onDependenciesChanged(): void;
    subscribe(onChange: (v: V) => any): void;
    unsubscribe(onChange: (v: V) => any): void;
    toString(): string;
    protected forceDeref(): V;
    private tryInvalidate;
}
/**
 * Declare a subscription that computes its value using the given function. The
 * returned value is a function that can be invoked with the same parameters as
 * `fn` and returns an `IRef<V>` for the value returned by your `fn`.
 */
export declare function sub<V, P extends Params = []>(fn: SubFn<V, P>): Subscription<V, P>;