_INSTANTIATING CODE PATTERNS_
by Fred Wild

Listing Four

#include "pets.hxx"

//////////////////////////////////////////////////////////
//     class PetOwner
PetOwner::PetOwner()
{
   m_Pet = NULL;
   m_Vet = NULL;
}
PetOwner::PetOwner(const PetOwner& obj)
{
   m_Name = obj.m_Name;
   m_Pet = obj.m_Pet->makeCopy();
   m_Vet = obj.m_Vet;
}
PetOwner *PetOwner::makeCopy() const 
{
    return new PetOwner(*this);
}
PetOwner::~PetOwner()
{
   delete m_Pet ;
}
PetOwner &
PetOwner::operator=(const PetOwner &rhs)
{
   if (this == &rhs) return *this ;
       // No changes if assignment to self 
   m_Name = rhs.m_Name;
   m_Pet = rhs.m_Pet->makeCopy();
   m_Vet = rhs.m_Vet;

   return *this ;
}
//////////////////////////////////////////////////////////
//     class Veterinarian

Veterinarian::Veterinarian()
{
}
Veterinarian::Veterinarian(const Veterinarian& obj)
{
   m_Name = obj.m_Name;
   m_StreetAddress = obj.m_StreetAddress;
   m_Town = obj.m_Town;
   m_Phone = obj.m_Phone;
}
Veterinarian *Veterinarian::makeCopy() const 
{
    return new Veterinarian(*this);
}
Veterinarian::~Veterinarian()
{
}
Veterinarian &
Veterinarian::operator=(const Veterinarian &rhs)
{
   if (this == &rhs) return *this ;
       // No changes if assignment to self 
   m_Name = rhs.m_Name;
   m_StreetAddress = rhs.m_StreetAddress;
   m_Town = rhs.m_Town;
   m_Phone = rhs.m_Phone;

   return *this ;
}
//////////////////////////////////////////////////////////
//     class Pet
Pet::Pet()
{
}
Pet::Pet(const Pet& obj)
{
   m_Name = obj.m_Name;
   m_KindOfPet = obj.m_KindOfPet;
}
Pet *Pet::makeCopy() const 
{
    return new Pet(*this);
}
Pet::~Pet()
{
}
Pet &
Pet::operator=(const Pet &rhs)
{
   if (this == &rhs) return *this ;
       // No changes if assignment to self 
   m_Name = rhs.m_Name;
   m_KindOfPet = rhs.m_KindOfPet;

   return *this ;
}