interface AttributeMap { [key: string]: unknown; } declare namespace AttributeMap { function compose(a?: AttributeMap, b?: AttributeMap, keepNull?: boolean): AttributeMap | undefined; function diff(a?: AttributeMap, b?: AttributeMap): AttributeMap | undefined; function invert(attr?: AttributeMap, base?: AttributeMap): AttributeMap; function transform(a: AttributeMap | undefined, b: AttributeMap | undefined, priority?: boolean): AttributeMap | undefined; } export default AttributeMap;