/**
 * An empty stand-in for a slot whose owning child component's render was
 * skipped (NestingComponents' skip-render optimization) — tells the client
 * "this fragment didn't change, don't touch it" via mode: 'skip' instead of
 * sending the slot's actual content again.
 * PHP parity: PlaceholderSlot
 */
export declare class PlaceholderSlot {
    name: string;
    componentId: string;
    parentComponentId: string | null;
    constructor(name: string, componentId: string, parentComponentId?: string | null);
    getName(): string;
    getComponentId(): string;
    getParentId(): string | null;
    toHtml(): string;
}