export declare const hasClass: (clz: string, attrs: null | [
    string,
    string
][]) => boolean | undefined;
export declare const readAttrValue: (name: string, attrs: null | [
    string,
    string
][]) => string | undefined;
export declare const addClass: (clz: string, attrs: null | [
    string,
    string
][]) => [
    string,
    string
][];