APP_NAMESPACE do nothing..

Hi
I notice that there is no Namespace at the Home controller which is strange and I hope that it is just a temporary thing..
I tested the constant APP_NAMESPACE, but it doesn't do anything or at least I can't figure it out what its doing..

In my case I set APP_NAMESPACE to be "Testapp".
When I list all declared classes inside the controller Home .. 

Home exists only as \Home with no namespace, as its declared at first place.
And the APP_NAMESPACE Testapp is not listed at all inside the declared class list.

At the same time if I try to declare the App Namespace inside the controller everything dies..


What is the idea of that APP_NAMESPACE?
And why App/Controller/Home.php doesn't have any Namespace declaration ?

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