Is there a shorter way to forward declare a class in a namespace?

I can forward declare a function in a namespace by doing this:

void myNamespace::doThing();

which is equivalent to:

namespace myNamespace
{
  void doThing();
}

To forward declare a class in a namespace:

namespace myNamespace
{
  class myClass;
}

Is there a shorter way to do this? I was thinking something along the lines of:

class myNamespace::myClass;