export interface ClassHelper {
    _prefixCls: string;
    _classList: any[];
    _el: HTMLElement;
    nativeElement: any;
    _setClassMap(): void;
}
export declare function isNotNil(value: any): boolean;
export declare function toCamelCase(str: any): any;
export declare function underscoreToCamelCase(str: any): any;
export declare function toBoolean(value: boolean | string): boolean;
export declare function toNumber<D>(value: number | string, fallback: D): number | D;
export declare function InputBoolean(): any;
export declare function simpleCheckForValidColor(data: any): any;
export declare function toState(data: any, oldHue?: number): {
    hsl: any;
    hex: string;
    rgb: any;
    hsv: any;
    oldHue: any;
    source: any;
};
export declare function isValidHex(hex: string): any;
export declare function getContrastingColor(data: any): "#fff" | "rgba(0,0,0,0.4)" | "#000";
export declare function render(c1: string, c2: string, size: number): string;
export declare function getCheckerboard(c1: string, c2: string, size: number): string;
export declare function isPromise(obj: {} | void): boolean;