interface CheckError extends Error {
    [key: string]: unknown;
}
declare function check(condition: unknown, message: string | Record<string, unknown>): asserts condition;
declare function is<T>(value: T): value is NonNullable<T>;
declare function checkWith<E extends Error>(ErrorClass: new (message: string) => E, condition: unknown, message: string): asserts condition;

export { type CheckError, check, checkWith, is };