	/**
	 * @callback ClassMapper
	 * @param {string} className
	 * @param {string} language
	 * @returns {string}
	 *
	 * @callback ClassAdder
	 * @param {ClassAdderEnvironment} env
	 * @returns {undefined | string | string[]}
	 *
	 * @typedef ClassAdderEnvironment
	 * @property {string} language
	 * @property {string} type
	 * @property {string} content
	 */