function Processor() {
    var plugins = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : [];

    _classCallCheck(this, Processor);

    /**
     * @member {string} - Current PostCSS version.
     *
     * @example
     * if ( result.processor.version.split('.')[0] !== '6' ) {
     *   throw new Error('This plugin works only with PostCSS 6');
     * }
     */
    this.version = '6.0.21';
    /**
     * @member {pluginFunction[]} - Plugins added to this processor.
     *
     * @example
     * const processor = postcss([autoprefixer, precss]);
     * processor.plugins.length //=> 2
     */
    this.plugins = this.normalize(plugins);
  }
@param {Array.<Plugin|pluginFunction>|Processor} plugins - PostCSS
       plugins. See {@link Processor#use} for plugin format.