26 lines
917 B
C++
26 lines
917 B
C++
// Copyright (C) 2015 Jérôme Leclercq
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// This file is part of the "Nazara Engine - Core module"
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// For conditions of distribution and use, see copyright notice in Config.hpp
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#pragma once
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#ifndef NAZARA_OFFSETOF_HPP
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#define NAZARA_OFFSETOF_HPP
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// Par "Jesse Good" de SO:
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// http://stackoverflow.com/questions/12811330/c-compile-time-offsetof-inside-a-template?answertab=votes#tab-top
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template <typename T, typename M> T NzImplGetClassType(M T::*);
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template <typename T, typename M> M NzImplGetMemberType(M T::*);
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template <typename T, typename R, R T::*M>
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std::size_t NzImplOffsetOf()
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{
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///FIXME: reinterpret_cast is not allowed in constexpr functions
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return reinterpret_cast<std::size_t>(&((static_cast<T*>(0))->*M));
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}
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#define NzOffsetOf(type, member) NzImplOffsetOf<decltype(NzImplGetClassType(&type::member)), decltype(NzImplGetMemberType(&type::member)), &type::member>()
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#endif // NAZARA_OFFSETOF_HPP
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