namespaces, classes and free functions - when do you need fully qualified names

Question

In my example below, why do I have to fully qualify the name of the free function in the cpp to avoid linker errors and why does it work for the class function without? Can you

Answer 1

When implementing a function it is usually preferable, I find, to open the namespace. Remember you can re-open them...

// in Test.cpp
namespace Test
{
   int FreeFunction()
   {
       return 0;
   }
}