export declare function assertDefined<T>(x: T | undefined, message?: string | Error | undefined): T;
export declare function assertNever(member: never, message?: string, stackCrawlMark?: AnyFunction): never;
type AnyFunction = (...args: never[]) => void;
export declare function fail(message?: string, stackCrawlMark?: AnyFunction): never;
export declare function assertSorted(a: readonly string[]): readonly string[];
export declare function assertSorted<T>(a: readonly T[], cb: (t: T) => string): readonly T[];
export declare function deepEquals(expected: unknown, actual: unknown): boolean;
export {};