use MyNamespace\CURLFile;

new CURLFile();

$ arc lint test.php
   Error  (XHP45) PHP Compatibility
    This codebase targets PHP 5.2.3, but `CURLFile` was not introduced until
    PHP 5.5.0.

               2
               3 use MyNamespace\CURLFile;
               4
    >>>        5 new CURLFile();