如果在编译时间评估该函数和运行时异常，则该如何给出编译错误？

发布于 2025-01-20 20:42:12 字数 702 浏览 1 评论 0原文

如果我具有可以在运行时提高异常的constexPR函数，则如果在编译时对其进行评估，我希望能够给出编译错误。

#include <stdexcept>
#include <type_traits>

constexpr void func (const int x)
{
    if (x == 0) {
        if (std::is_constant_evaluated()) {
            /// compile error
        } else {
            throw std::invalid_argument("x cannot be 0.");
        }
    }
}

我尝试将static_assert放入if语句中，但是无论if语句如何，它都会对其进行评估（因为我假设的IF不是constexpr）。我还尝试了static_assert（x！= 0）;，但是它告诉我静态断言的非恒定条件（这有意义...？）。

有没有（最好简单）这样做的方法？谢谢。

编辑：我概括了功能，在我的情况下，我有一个构造函数，我需要使用它来生成编译时间和运行时间对象。因此，如果我尝试创建一个以x为0的constexpr对象，则我希望该程序在x之类的消息中给出编译错误。

原文

If I have a constexpr function that can raise an exception at runtime, I want to make it able to give a compile error if it's evaluated at compile time.

#include <stdexcept>
#include <type_traits>

constexpr void func (const int x)
{
    if (x == 0) {
        if (std::is_constant_evaluated()) {
            /// compile error
        } else {
            throw std::invalid_argument("x cannot be 0.");
        }
    }
}

I have tried putting static_assert inside the if statement, but it evaluates it regardless of the if statement (since the if is not constexpr I'm assuming). I have also tried static_assert(x != 0);, but it tells me non-constant condition for static assertion (which makes some sense...?).

Is there any (preferably easy) way to do this? Thanks.

EDIT: I generalized the function, in my case I have a constructor that I need to use to generate both compile time and run time objects. So I would like the program to give a compile error with a message like x cannot be 0 if I try to create a constexpr object with x being 0.

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