import { AsyncReturnType } from './promises';
import { ExtensibleFunction } from './extensibleFunction';
type EFFunc = (...[]: Iterable<any>) => any;
type LoadState = 'unloaded' | 'loading' | 'loaded' | 'error';
interface EnsureFuncOptions<F extends EFFunc> {
    initialValue?: AsyncReturnType<F>;
    initialState: LoadState;
    fetchOnAccess: boolean;
}
/**
 * A Class for helping with fetching remote data and tracking status.
 * When the object is called (either directly or via .ensure()), it executes the function that was given during construction, and return a Promise.
 *
 * `state` is transitioned to 'loading' until the function returns, whereon `state` is transitioned to 'loaded' or 'error'.
 */
export declare class EnsureFunction<F extends EFFunc> extends ExtensibleFunction<Parameters<F>, Promise<ReturnType<F>>> {
    constructor(func: F);
    constructor(options: Partial<EnsureFuncOptions<F>>, func: F);
    private options;
    private func;
    currentPromise: Promise<AsyncReturnType<F>>;
    accessor _value: AsyncReturnType<F>;
    accessor error: any;
    accessor state: LoadState;
    _call(args: Parameters<F>): Promise<any>;
    get value(): AsyncReturnType<F>;
    markLoaded(): void;
    setValue(value: AsyncReturnType<F>): void;
    ensure(...args: Parameters<F>): Promise<any>;
    reload(...args: Parameters<F>): Promise<any>;
    reset(keepValue?: boolean): void;
}
export {};