code: function initUse (Vue) {
    Vue.use = function (plugin) {
      var installedPlugins = (this._installedPlugins || (this._installedPlugins = []));
      if (installedPlugins.indexOf(plugin) > -1) {
        return this
      }
  
      // additional parameters
      var args = toArray(arguments, 1);
      args.unshift(this);
      if (typeof plugin.install === 'function') {
        plugin.install.apply(plugin, args);
      } else if (typeof plugin === 'function') {
        plugin.apply(null, args);
      }
      installedPlugins.push(plugin);
      return this
    };
  }
docs: /*