pimpl.cpp

struct Renderable {
  virtual Image render(unsigned const width) const = 0;
  virtual ~Renderable() {}
};

template<class T>
struct Model : Renderable {
  
  T data;
  
  Model(T const& data)
    : data{ data }
  {}
  
  virutal ComponentModel() {}
};

struct Component : Renderable {
  
  template<class T>
  Component(T data) 
    : pimpl{make_shared<Model<T>>(data)}
  {}
 
  virtual Image render(unsigned const width) const {
   return pimpl->render(width);
  }
 
  shared_ptr<Renderable> pimpl; 
};