code: function Tag$2(el, opts) {
    // get the tag properties from the class constructor
    var ref = this;
    var name = ref.name;
    var tmpl = ref.tmpl;
    var css = ref.css;
    var attrs = ref.attrs;
    var onCreate = ref.onCreate;
    // register a new tag and cache the class prototype
    if (!__TAG_IMPL[name]) {
      tag$1(name, tmpl, css, attrs, onCreate);
      // cache the class constructor
      __TAG_IMPL[name].class = this.constructor;
    }
  
    // mount the tag using the class instance
    mountTo(el, name, opts, this);
    // inject the component css
    if (css) { styleManager.inject(); }
  
    return this
  }
docs: Another way to create a riot tag a bit more es6 friendly
  @param { HTMLElement } el - tag DOM selector or DOM node/s
  @param { Object } opts - tag logic
  @returns { Tag } new riot tag instance