C++11里实现is_constexpr

流星-圣殿 2018-07-10 09:42:53

就是判断一个对象究竟是不是constexpr。
网上有一个实现，但是只能在C++14下测试通过，11下不行：

template <class T>
constexpr void test_helper(T&& t) {}

#define IS_CONSTEXPR(...) noexcept(test_helper(__VA_ARGS__))

看看大家有办法没？

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