import type { StyleValue } from "vue";
import { Data } from "./types";
export type { StyleValue } from "vue";
export type ClassValue = string | ClassValue[] | Record<string, boolean> | undefined | null;
export declare const capitalize: <T extends string>(str: T) => Capitalize<T>;
export declare const extend: {
    <T extends {}, U>(target: T, source: U): T & U;
    <T_1 extends {}, U_1, V>(target: T_1, source1: U_1, source2: V): T_1 & U_1 & V;
    <T_2 extends {}, U_2, V_1, W>(target: T_2, source1: U_2, source2: V_1, source3: W): T_2 & U_2 & V_1 & W;
    (target: object, ...sources: any[]): any;
};
export declare const isArray: (arg: any) => arg is any[];
export declare const isFunction: (val: unknown) => val is Function;
export declare const isObject: (val: unknown) => val is Record<any, any>;
export declare const isPromise: <T = any>(val: unknown) => val is Promise<T>;
export declare const toHandlerKey: <T extends string>(str: T) => T extends "" ? "" : `on${Capitalize<T>}`;
export declare const isInstanceOf: (propTypes: (new (...args: any[]) => any)[], value: any) => boolean;
export declare function mergeProps(...args: Data[]): Data;
export declare function normalizeClass(value: ClassValue): string;
export type NormalizedStyle = Record<string, string | number>;
export declare function normalizeStyle(value: StyleValue): NormalizedStyle | string | undefined;
export declare function parseStringStyle(cssText: string): NormalizedStyle;
export declare const isString: (val: unknown) => val is string;
export declare const isOn: (key: string) => boolean;