export declare type HashSet = Set<string>;
export declare function createHashSet(): HashSet;
export declare function hashSetContains(key: string, set: HashSet): boolean;
export declare function addHashSetItem(key: string, set: HashSet): HashSet;
export declare function removeHashSetItem(key: string, set: HashSet): HashSet;
export declare function mergeHashSets(set1: Set<string>, set2: Set<string>): Set<string>;