How to reduce duplications of code while template partial specialization

0-Avoid of codes duplications in template partial specialization.md

• 1-specialization-static.cxx
• 2-specialization-module-simple.cxx
• 3-specialization-module-full.cxx
• 4-specialization-Inherit.cxx
• z-result.txt

1-specialization-static.cxx

#include<iostream>
using namespace std;

template<class T, int I>
class MyClassB;

// HELPER
template<class T, int I>
struct MyClassBImpl{
  // You may be able to get a pointer of MyClassBImpl as a parameter
  static void Impl(){ 
    cout<<"Constructor of MyClassBImpl : default"<<endl; 
  }
  static void doSomething(){
    cout<<"doSomething in MyClassBImpl : default"<<endl;
  }
};
template<class T>
struct MyClassBImpl<T,1> {
  static void Impl(){ 
    cout<<"Constructor of MyClassBImpl : I==1"<<endl; 
  }
  static void doSomething(){
    cout<<"doSomething in MyClassBImpl : I==1"<<endl;
  }
};

// TEMPLATE
template<class T, int I>
class MyClassB {
public:
  MyClassB(){ MyClassBImpl<T,I>::Impl(); }
  void doSomething(){ 
    MyClassBImpl<T,I>::doSomething();
  };
};

// TEST
int main(){
  MyClassB<int, 1> a1;
  MyClassB<int, 2> a2;
  MyClassB<int, 3> a3;
  a1.doSomething();
  a2.doSomething();
  a3.doSomething();
}

2-specialization-module-simple.cxx

#include<iostream>
using namespace std;

template<class T, int I>
class MyClassB;

// HELPER
template<class T, int I>
struct MyClassBImpl{
  MyClassBImpl(){ 
    cout<<"Constructor of MyClassBImpl : default"<<endl; 
  }
  void doSomething(){
    cout<<"doSomething in MyClassBImpl : default"<<endl;
  }
};
template<class T>
struct MyClassBImpl<T,1> {
  MyClassBImpl(){ 
    cout<<"Constructor of MyClassBImpl : I==1"<<endl; 
  }
  void doSomething(){
    cout<<"doSomething in MyClassBImpl : I==1"<<endl;
  }
};

// TEMPLATE
template<class T, int I>
class MyClassB {
public:
  MyClassB():fImpl(){}
  void doSomething(){ 
    fImpl.doSomething();
  };
private:
  MyClassBImpl<T,I> fImpl; 
};

// TEST
int main(){
  MyClassB<int, 1> a1;
  MyClassB<int, 2> a2;
  MyClassB<int, 3> a3;
  a1.doSomething();
  a2.doSomething();
  a3.doSomething();
}

3-specialization-module-full.cxx

#include<iostream>
using namespace std;

template<class T, int I>
class MyClassB;

// HELPER
template<class T, int I>
class MyClassBImpl{
public:
  MyClassBImpl( MyClassB<T,I> *m):fMother(m){ 
    cout<<"Constructor of MyClassBImpl : default"<<endl; 
  }
  void doSomething(){
    cout<<"doSomething in MyClassBImpl : default"<<endl;
  }
private:
  MyClassB<T,I> *fMother;
};
template<class T>
class MyClassBImpl<T,1> {
public:
  MyClassBImpl( MyClassB<T,1> *m):fMother(m){ 
    cout<<"Constructor of MyClassBImpl : I==1"<<endl; 
  }
  void doSomething(){
    cout<<"doSomething in MyClassBImpl : I==1"<<endl;
  }
private:
  MyClassB<T,1> *fMother;
};

// TEMPLATE
template<class T, int I>
class MyClassB {
public:
  MyClassB():fImpl(this){}
  void doSomething(){ 
    fImpl.doSomething();
  };
private:
  MyClassBImpl<T,I> fImpl; 
};

// TEST
int main(){
  MyClassB<int, 1> a1;
  MyClassB<int, 2> a2;
  MyClassB<int, 3> a3;
  a1.doSomething();
  a2.doSomething();
  a3.doSomething();
}

4-specialization-Inherit.cxx

#include<iostream>
using namespace std;

template<class T, int I>
class MyClassB;

// Base Template Class
template<class T, int I>
class MyClassB {
public:
  MyClassB(){}
  virtual void doSomething(){}
};


// Inherited Implementation
template<class T, int I>
class MyClassBImpl : public MyClassB<T,I>{
public:
  MyClassBImpl():MyClassB<T,I>(){ 
    cout<<"Constructor of MyClassBImpl : default"<<endl; 
  }
  virtual void doSomething(){
    cout<<"doSomething in MyClassBImpl : default"<<endl;
  }
};

template<class T>
class MyClassBImpl<T,1> : public MyClassB<T,1> {
public:
  MyClassBImpl():MyClassB<T,1>(){ 
    cout<<"Constructor of MyClassBImpl : I==1"<<endl; 
  }
  virtual void doSomething(){
    cout<<"doSomething in MyClassBImpl : I==1"<<endl;
  }
};

// TEST
int main(){
  MyClassBImpl<int, 1> a1; 
  MyClassBImpl<int, 2> a2; 
  MyClassBImpl<int, 3> a3;
  a1.doSomething();
  a2.doSomething();
  a3.doSomething();
}

z-result.txt

Constructor of MyClassBImpl : I==1
Constructor of MyClassBImpl : default
Constructor of MyClassBImpl : default
doSomething in MyClassBImpl : I==1
doSomething in MyClassBImpl : default
doSomething in MyClassBImpl : default