import type { IConfigCatCache } from "../ConfigCatCache.js";
interface ILocalStorage {
    setItem(key: string, value: string): void;
    getItem(key: string): string | null;
}
export declare class LocalStorageConfigCache implements IConfigCatCache {
    private readonly storage;
    private static tryGetFactory;
    constructor(storage: ILocalStorage);
    set(key: string, value: string): void;
    get(key: string): string | undefined;
}
export declare function getLocalStorage(): ILocalStorage | undefined;
export declare function toUtf8Base64(str: string): string;
export declare function fromUtf8Base64(str: string): string;
export {};