import { Loader, LoaderOptions } from './Loader';
import { ActionImpl } from '../action/ActionImpl';
/**
 * A `Loader` can follow the changes in some input data, and prepare some output data accordingly.
 *
 * Let's assume that there is a value ("output") that depends on some other value ("input"),
 * and can be derived from it using an asynchronous function.
 *
 * One example would be loading some data from an external source, based on an ID or other criteria.
 *
 * A `Loader` can do this for you: it watches the input, and maintains the output accordingly.
 */
export declare class LoaderImpl<Input, Output> implements Loader<Input, Output> {
    private readonly _options;
    private readonly _logger;
    constructor(_options: LoaderOptions<Input, Output>);
    /**
     * The last input value that we have seen
     *
     * ... and fetched data for, or decide to skip
     */
    private _fetchedForInput?;
    private _checkedAt?;
    private get __hasInputChanged();
    private get _cacheTime();
    private get _areWeUpToDate();
    private _relaxing;
    /**
     * Relax, stop following changes
     */
    relax(): void;
    private _tick;
    private _clearSchedule;
    private _scheduleNext;
    /**
     * Internal loader wrapping the loading
     * @private
     */
    private readonly _load;
    private _fetchIfWeHaveTo;
    /**
     * Make sure that we are up-to-date!
     *
     *      * ... unless we are sleeping. If we are sleeping, do nothing.
     */
    private _update;
    readonly refresh: ActionImpl;
    private _sleeping;
    private _timer;
    /**
     * Start to listen
     */
    init(): void;
    /**
     * Get the current input
     */
    get input(): Input | undefined;
    /**
     * Find out if we should skip loading
     */
    private get _shouldSkip();
    /**
     * Are we loading now?
     */
    get loading(): boolean;
    get errorMessage(): string | undefined;
    _value?: Output;
    /**
     * Return the value
     */
    get value(): Output | undefined;
    setValue(value?: Output): void;
}