improve @user directive

Author: reziamini

src/Directives/UserDirective.php

@@ -10,6 +10,6 @@ class UserDirective implements Directive
     public static function handle($parameter)
     {
         $parameter = str_replace(['"', "'"], null, $parameter);
-        return "<?php echo \auth()->user()->$parameter; ?>";
+        return "<?php if(\auth()->check()): echo \auth()->user()->{$parameter}; endif; ?>";
     }
 }