import type { CandidateChange } from './types.js';
export declare class CandidateIndex {
    private readonly candidatesBySource;
    sync(sourceId: string, candidates: Iterable<string>): CandidateChange;
    remove(sourceId: string): CandidateChange;
    values(): Set<string>;
    get(sourceId: string): Set<string>;
    entries(): Map<string, Set<string>>;
    clear(): void;
}