- Solution

// TypeErasureTypeInfo.cpp
#include <iostream>
#include <memory>
#include <string>
#include <typeinfo>
#include <vector>
struct Object{
   std::string getTypeName() const { return _inner->getTypeName(); }
   struct Concept{
      using ptr = std::unique_ptr<Concept>;
      virtual std::string getTypeName() const = 0;
   };
   template <typename T> 
   struct Model : Concept{
      std::string getTypeName() const override { return typeid(T).name(); }
   };
private:
   typename Concept::ptr _inner;
};
template <>
struct Object::Model<long long> : Object::Concept{
	std::string getTypeName() const override { return "long long";}
};
template <>
struct Object::Model<std::string> : Object::Concept{
	std::string getTypeName() const override { return "std::string<char>";}
};
template <>
struct Object::Model<std::vector<int>> : Object::Concept{
	std::string getTypeName() const override { return "std::vector<int>";}
};
	
template <typename T>
void printType(T&& t){
   std::cout << t.getTypeName() << std::endl;
}
class Test{};
int main(){
   
   printType(Object::Model<int>{});
   printType(Object::Model<double>{});
   printType(Object::Model<void>{});
   printType(Object::Model<Test>{});
   printType(Object::Model<Object>{});
   printType(Object::Model<long long>{});
   printType(Object::Model<std::string>{});
   printType(Object::Model<std::vector<int>>{});   
    
}