type ValueStringType = 'string' | 'number' | 'boolean' | 'boolean|string' | 'number|string' | 'any';
type ValueType<T extends ValueStringType> = T extends 'string' ? string : T extends 'number' ? number : T extends 'boolean' ? boolean : T extends 'boolean|string' ? boolean | string : T extends 'number|string' ? number | string : any;
/**
 * Static class to access environment variables and configuration files.
 *
 * This class can also be used as a service.
 *
 * @export
 * @class Config
 */
export declare class Config {
    /**
     * Read the configuration value associated with the given key. Optionaly check its type.
     *
     * @static
     * @template T
     * @param {string} key - The configuration key.
     * @param {T} [type] - The expected type of the returned value.
     * @param {ValueType<T>} [defaultValue] - A default value if none is found.
     * @returns {ValueType<T>|undefined} The configuration value
     * @memberof Config
     */
    static get<T extends ValueStringType>(key: string, type: T, defaultValue: ValueType<T>): ValueType<T>;
    static get<T extends ValueStringType>(key: string, type?: T): ValueType<T> | undefined;
    /**
     * Read the configuration value associated with the given key. Optionaly check its type.
     *
     * Throw an ConfigNotFoundError if no value is found.
     *
     * @static
     * @template T
     * @param {string} key - The configuration key.
     * @param {T} [type] - The expected type of the returned value.
     * @param {string} [msg] - The message of the ConfigNotFoundError if no value is found.
     * @returns {ValueType<T>} The configuration value.
     * @memberof Config
     */
    static getOrThrow<T extends ValueStringType>(key: string, type?: T, msg?: string): ValueType<T>;
    /**
     * Clear the cache of the loaded files.
     *
     * @static
     * @memberof Config
     */
    static clearCache(): void;
    static set(key: string, value: string | number | boolean): void;
    static remove(key: string): void;
    private static yaml;
    private static config;
    private static testConfig;
    private static readJSON;
    private static readYAML;
    private static readJS;
    private static readConfigValue;
    private static mergeDeep;
    private static getYAMLInstance;
}
export {};