Description:
------------
---
From manual page: http://www.php.net/language.oop5.typehinting
---
    /**
     * First parameter must be iterator
     */
    public function test_interface(Traversable $iterator) {
        echo get_class($iterator);
    }

The comment in the example is slightly imprecise, what is a particular problem
for the German translation, for example (en. iterator = ge. Iterator). I suggest
to reword:

  "First parameter must be a Traversable"