export interface Hashable {
    hash(): number;
    equals(other: Hashable): boolean;
    /** Optional string key used as a secondary lookup index in EqualityMap. */
    key?: string;
}
export declare const CACHE_KEY_SEPARATOR = "::";
export declare class EqualityMap<K extends Hashable, V> {
    private readonly buckets;
    private _size;
    private readonly equals;
    private readonly keyExtractor?;
    private readonly keyMap?;
    constructor(source?: EqualityMap<K, V>, keyExtractor?: (k: K) => string | undefined);
    has(key: K): boolean;
    get(key: K): V | null | undefined;
    private syncKeyIndex;
    set(key: K, value: V | null | undefined): this;
    setAll(source: EqualityMap<K, V>): this;
    delete(key: K): boolean;
    get size(): number;
    clear(): void;
    getOrCompute(key: K, computeFn: (key: K) => V | null): V | null;
    keys(): IterableIterator<K>;
    values(): IterableIterator<V | null | undefined>;
    tuples(): IterableIterator<[K, V | null | undefined]>;
    getByKey(stringKey: string): K | undefined;
}