export declare const isNonNullable: <T>(val: T) => val is NonNullable<T>;
export declare const isNumber: (val: any) => val is number;
export declare const isString: (val: any) => val is string;
export declare const isPlainObject: <T extends object = object>(val: any) => val is T;
export declare const isFunction: (val: any) => val is (...args: any[]) => any;
export declare const isThenable: <T>(val?: PromiseLike<T>) => val is PromiseLike<T>;
export declare const isPrimitive: (val: any) => boolean;