Using Class Templates with Fake Parameters in Derived Classes.

#include <iostream>
#include "FakeTemplateException.h"

//test customer exception
static void Test( int n );
static void catchException(int n);


//define 2 Exception classes 
struct DerivedException1_Tag {};
typedef DerivedException<DerivedException1_Tag>  DerivedException1; 

struct DerivedException2_Tag {};
typedef DerivedException<DerivedException2_Tag>  DerivedException2; 

struct DerivedException3_Tag {};
typedef DerivedException<DerivedException3_Tag>  DerivedException3; 

int main()
{
  for(int i = 1; i < 3; ++i)
    catchException(i);
  return 0;
}

void catchException(int n)
{
  try
  {
   Test(n);
  }
  catch(const DerivedException1& e1)
  { 
    std::cerr << "CATCH DerivedException1" << std::endl;
    std::cerr << e1.what()  << std::endl; 
  }
  catch(const DerivedException2& e2)
  { 
    std::cerr << "CATCH DerivedException2" << std::endl;
    std::cerr << e2.what()  << std::endl; 
  }
  return;
}

void Test( int n )
{
  switch( n)
  {
    case 1:
      {
       DerivedException1 e1;
        throw(e1);
      }
      break;
    case 2:
      {
      DerivedException2 e2("this is DerivedException2");
      throw(e2);
      }
      break;
     default:
      {
        DerivedException3 e3("this is never happen");
        throw(e3);
      }
      break;

  }
  return;
}