import type { InViewportConfigCheckFn, InViewportConfigDirections } from '../types';
export declare const isObject: (value: unknown) => value is Record<string | number | symbol, any>;
export declare const isNotEmptyArray: <T = any>(value: unknown) => value is T[];
export declare function isPlatformBrowser(): boolean;
export declare function isPlatformServer(): boolean;
export declare function toBase64Browser(input: string): string;
export declare const toBase64Server: (input: string) => string;
export declare const toBase64: (input: string) => string;
export declare const stringifyObject: (input: unknown) => string;
export declare const withRoot: (value: unknown) => Element | undefined;
export declare const withRootMargin: (value: unknown) => string;
export declare const isValidThreshold: (value: unknown) => value is number;
export declare const withThreshold: (value: unknown) => number[];
export declare const withPartial: (partial?: unknown) => boolean;
export declare const isValidDirection: (value: unknown) => value is InViewportConfigDirections;
export declare const withDirection: (value: unknown) => InViewportConfigDirections;
export declare const withCheckFn: (value: unknown) => InViewportConfigCheckFn | undefined;
