is_ptr_base_of.h

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/****************************************************************************
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** Copyright (C) 2013 Lionel Marty (contact@qxorm.com)
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#ifndef _QX_IS_PTR_BASE_OF_H_
#define _QX_IS_PTR_BASE_OF_H_

#ifdef _MSC_VER
#pragma once
#endif

namespace qx {
namespace trait {

template <typename B, typename D>
class is_ptr_base_of
{

private:

   template <typename V, typename W>
   static typename std::conditional<std::is_base_of<V, W>::value, char, int>::type removePtr(const volatile V * const volatile, const volatile W * const volatile);

   static int removePtr(...);
   static B b;
   static D d;

public:

   enum { value = (std::is_pointer<B>::value && std::is_pointer<D>::value && (sizeof(qx::trait::is_ptr_base_of<B, D>::removePtr(b, d)) == sizeof(char))) };

   typedef typename std::conditional<qx::trait::is_ptr_base_of<B, D>::value, std::true_type, std::false_type>::type type;

};

} // namespace trait
} // namespace qx

#endif // _QX_IS_PTR_BASE_OF_H_