export declare function assertNonNullable<T>(value: T, failMessage?: string): asserts value is NonNullable<T>;
export declare function assertNullable<T extends INullable = INullable>(value: unknown, failMessage?: string): asserts value is T;
export declare function isNonNullable<T>(value: T): value is NonNullable<T>;
export declare function isNullable<T extends INullable = INullable>(value: unknown): value is T;
type INullable = null | undefined;
export type Nullable<T> = T | INullable;
export declare const withoutNullable: <T extends object>(target: T) => Required<T>;
export {};