#pragma once
#include <type_traits>
#include "dxxsconf.h"
template <typename T>
class exact_type
{
T *p;
public:
operator bool() const = delete;
// Conversion to void* variants is prohibited
operator void *() const = delete;
operator volatile void *() const = delete;
operator const void *() const = delete;
operator const volatile void *() const = delete;
template <typename U>
bool operator<(U &&) const = delete;
template <typename U>
bool operator<=(U &&) const = delete;
template <typename U>
bool operator>(U &&) const = delete;
template <typename U>
bool operator>=(U &&) const = delete;
template <typename U>
bool operator!=(U &&rhs) const { return !operator==(static_cast<U &&>(rhs)); }
exact_type(T *t) : p(t) {}
// Conversion to the exact type is permitted
operator const T *() const { return p; }
operator typename std::remove_const<T>::type *() const { return p; }
bool operator==(const T *rhs) const { return p == rhs; }
};
template <typename T>
class prohibit_void_ptr
{
public:
// Return a proxy when the address is taken
exact_type<T> operator&() { return static_cast<T*>(this); }
exact_type<T const> operator&() const { return static_cast<T const*>(this); }
};