C++ Properties (magic get/set)

main.cpp

#include <iostream>
#include <functional>
#include <utility>

using namespace std;

template <class T>
class property{
  public:
    using setter_type = function<void(T&, const T&)>;
    using getter_type = function<T&(T&)>;

  protected:
    getter_type getter;
    setter_type setter;
    T value;

  public:
    /*template <class... Args>
    property(getter_type get, setter_type set, Args&&... args) : getter{get}, setter{set}, value{std::forward<Args>(args)...} {
      cout << "constructed";
    }*/

    template <class U>
    property(getter_type get, setter_type set, U&& arg) : getter{get}, setter{set}, value{std::forward<U>(arg)} {
    }

    /*template <class... Args>
    property(Args&&... args) : property(
      defaultGetter,
      defaultSetter,
      std::forward<Args>(args)...
    ){}*/

    operator T&(){
      return this->getter(this->value);
    }

    property& operator=(const T& rhs){
      this->setter(this->value, rhs);
      return *this;
    }

  public:
    static setter_type noSetter;
    static getter_type defaultGetter;
    static setter_type defaultSetter;
};

template <class T, class... Args>
property<T> make_default_property(Args&&... args){
  return property<T>{
    property<T>::defaultGetter,
    property<T>::defaultSetter,
    T{std::forward<Args>(args)...}
  };
}

template <class T>
typename property<T>::setter_type property<T>::noSetter = [](T& value, const T& assignment){};


template <class T>
typename property<T>::getter_type property<T>::defaultGetter = [](T& value) -> T& {
  return value;
};

template <class T>
typename property<T>::setter_type property<T>::defaultSetter = [](T& value, const T& assignment){
  value = assignment;
};

property<int>::getter_type logGet = [](int& target) -> int&{
  printf("[GET] %i\n", target);
  return target;
};

property<int>::setter_type logSet = [](int& target, const int& assignment) -> void{
  printf("[SET] old: %i new: %i\n", target, assignment);
};

int main() {
  property<int> i{logGet, logSet, 0};
  std::cout << i << '\n';
}