/**
 * Adds a callback that's run when all assets are ready.
 * If all assets have already loaded, call the callback immediately.
 *
 * The first parameter of the callback function must be a function that
 * itself calls as a callback when it has finished.
 *
 * @param cb
 */
export function addCallback(cb: any): void;
/**
 * Add an expected asset to the list.
 *
 * @param {function} asset
 */
export function expect(asset: Function): void;
/**
 * As a bit of a hack this ensures the game starting callback is always
 * the last one.
 *
 * @param cb
 */
export function finalCallback(cb: any): void;
/**
 * When an asset has finished loading, this method should be called.
 *
 * @param asset The name of the asset that's ready
 * @returns {boolean} true if asset was expected
 */
export function finished(asset: any): boolean;