polymorphism.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
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 * Copyright(C) 2021-2026                                                    *
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#ifndef VCL_BASE_CONCEPTS_POLYMORPHISM_H
#define VCL_BASE_CONCEPTS_POLYMORPHISM_H
 
#include "pointers.h"
 
#include <concepts>
 
namespace vcl {
 
namespace detail {
 
// true if T is a shared_ptr, and the type pointed by T is a base of D
template<typename T, typename D>
concept IsSharedPtrOfBaseOf =
    IsSharedPointer<T> &&
    std::derived_from<D, std::remove_pointer_t<typename T::element_type>>;
 
} // namespace detail
 
template<typename T>
concept Cloneable = requires (T&& obj) {
    { obj.clone() } -> detail::IsSharedPtrOfBaseOf<std::remove_cvref_t<T>>;
};
 
} // namespace vcl
 
#endif // VCL_BASE_CONCEPTS_POLYMORPHISM_H