export type TextareaThemeVars = {
    textareaLineHeight?: string;
    textareaFontSize?: string;
    textareaColor?: string;
    textareaPlaceholderColor?: string;
    textareaReadonlyColor?: string;
    textareaLimitColor?: string;
    textareaLimitFontSize?: string;
    textareaLimitLineHeight?: string;
};
export declare function getStringLength(chars?: string): number;