code: function registerDirective(Vue, name, definition) {
          Vue._shards_vue_directives_ = Vue._shards_vue_directives_ || {};
          var loaded = Vue._shards_vue_directives_[name];
  
          if (!loaded && definition && name) {
              Vue._shards_vue_directives_[name] = true;
              Vue.directive(name, definition);
          }
  
          return loaded
      }
docs: Register a directive as being loaded. returns true if directive plugin already registered