/**
 * An observer for permission state changes.
 */
export interface PermissionObserver {
    /**
     * Wait for the permission state to change to one of the specified states.
     *
     * @param stateOrStates - The desired permission state(s).
     * @param task - An optional task to execute while waiting for the state
     *   change. You can use this to guarantee that certain actions are performed
     *   after observation has started.
     *
     * @returns A promise that resolves when the permission state matches one of
     *   the desired states. If the state is already one of the desired states,
     *   the promise resolves immediately.
     * @throws A {@link TypeError} if no states are provided.
     */
    waitForState: (stateOrStates: PermissionState | PermissionState[], task?: () => Promise<void>) => Promise<void>;
}
/**
 * Create an observer for a permission.
 *
 * @param permissions - The Permissions API to use.
 * @param descriptor - A descriptor of the permission to observe.
 *
 * @returns An observer for the permission.
 */
export declare function createPermissionObserver(permissions: Permissions, descriptor: PermissionDescriptor): PermissionObserver;