export interface DebouncedFunc<T extends (...args: any[]) => any> {
    /**
     * Call the original function, but applying the debounce rules.
     *
     * If the debounced function can be run immediately, this calls it and returns its return
     * value.
     *
     * Otherwise, it returns the return value of the last invokation, or undefined if the debounced
     * function was not invoked yet.
     */
    (...args: Parameters<T>): ReturnType<T> | undefined;
    /**
     * Throw away any pending invokation of the debounced function.
     */
    cancel(): void;
    /**
     * If there is a pending invokation of the debounced function, invoke it immediately and return
     * its return value.
     *
     * Otherwise, return the value from the last invokation, or undefined if the debounced function
     * was never invoked.
     */
    flush(): ReturnType<T> | undefined;
}
interface DebounceOptions {
    maxWait?: number;
    leading?: boolean;
    trailing?: boolean;
}
/**
 * Creates a debounced function that delays invoking `func` until after `wait`
 * milliseconds have elapsed since the last time the debounced function was
 * invoked, or until the next browser frame is drawn. The debounced function
 * comes with a `cancel` method to cancel delayed `func` invocations and a
 * `flush` method to immediately invoke them. Provide `options` to indicate
 * whether `func` should be invoked on the leading and/or trailing edge of the
 * `wait` timeout. The `func` is invoked with the last arguments provided to the
 * debounced function. Subsequent calls to the debounced function return the
 * result of the last `func` invocation.
 *
 * **Note:** If `leading` and `trailing` options are `true`, `func` is
 * invoked on the trailing edge of the timeout only if the debounced function
 * is invoked more than once during the `wait` timeout.
 *
 * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred
 * until the next tick, similar to `setTimeout` with a timeout of `0`.
 *
 * If `wait` is omitted in an environment with `requestAnimationFrame`, `func`
 * invocation will be deferred until the next frame is drawn (typically about
 * 16ms).
 *
 * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/)
 * for details over the differences between `debounce` and `throttle`.
 *
 * @param {Function} func The function to debounce.
 * @param {number} [wait=0]
 *  The number of milliseconds to delay; if omitted, `requestAnimationFrame` is
 *  used (if available).
 * @param {Object} [options={}] The options object.
 * @param {boolean} [options.leading=false]
 *  Specify invoking on the leading edge of the timeout.
 * @param {number} [options.maxWait]
 *  The maximum time `func` is allowed to be delayed before it's invoked.
 * @param {boolean} [options.trailing=true]
 *  Specify invoking on the trailing edge of the timeout.
 * @returns {Function} Returns the new debounced function.
 * @example
 *
 * // Avoid costly calculations while the window size is in flux.
 * window.addEventListener('resize', debounce(calculateLayout, 150))
 *
 * // Invoke `sendMail` when clicked, debouncing subsequent calls.
 * element.addEventListener('click', debounce(sendMail, 300, {
 *   'leading': true,
 *   'trailing': false
 * }))
 *
 * // Ensure `batchLog` is invoked once after 1 second of debounced calls.
 * const debounced = debounce(batchLog, 250, { 'maxWait': 1000 })
 * const source = new EventSource('/stream')
 * source.addEventListener('message', debounced)
 *
 * // Cancel the trailing debounced invocation.
 * window.addEventListener('popstate', debounced.cancel)
 *
 * // Check for pending invocations.
 * const status = debounced.pending() ? "Pending..." : "Ready"
 */
export declare function debounce<T extends (...args: any) => any>(func: T, wait?: number, options?: DebounceOptions): DebouncedFunc<T>;
export {};