How to place a class into a namespace

Why would you want to do that?

BTW I don't use namespaces because it increases the code size (the compiled, binary code) and it is important to me to keep it as small as possible in my datafield. 

Thank you for the super quick reply :-)

The idea is to keep everything at the right place - and also learning the language a bit better.

You may just put your classes into a separate folder to be them separated visually. If you would like to have also logical separation you may declare a module, like

module MyWatchUi {
    class CustomArc extends WatchUi.Drawable {
        ...
    }
}    

var ringSteps = View.findDrawableById("RingSteps") as MyWatchUi.CustomArc;

giving your client code the same namespace as system API classes have is not the best idea even if it's possible

If it's meant to be common between multiple apps, what I do is do the code as a barrel project, and then based on the main app, either pull it in as a barrel or pull in the mc file itself using jungles.

Hello SpitRider :-)

Thank you very much for your suggestion. I will create my own namespace.

My main aim is to have nice and readable code :-) Also because it is on Github and someone else should be able to understand the watchface.

Have a great day