Question

namespace t {
    class A {};
}

How can create an object of class A?

EDIT :

namespace beta {
  class TESSDLL_API TessBaseAPI 
  { 
     public: 
           TessBaseAPI(); 
           virtual ~TessBaseAPI(); 
  }
}

This is the class defined inside beta  namespace . Now how do i call the constructor? is

tess = new beta::TessBaseAPI(); 

correct?

Answer 1

Either

namespace t
{
    A a;
}

or

t::A a;

In the first case a lives inside namespace t (in fact its full name is ::t::a).
In the second case a is global.

(note: your class A{} is missing a ; after })