无法编译下面的代码：

#include <array>

template <class T, T state>
class stateless
{
public:

    void f() { /* do something with m_val*/; }

private:

    static inline constexpr T m_val = state;
};

struct A
{
    int x;

    int GetX() const { return x; }
};

template <class T, class ReturnType>
using FuncPtr = ReturnType(T::*)() const;

template <class T, class ReturnType>
class func_getter
{
public:

    using object_type = T;
    using value_type = ReturnType;

    using MyFuncPtr = FuncPtr<T, ReturnType>;

    constexpr func_getter(MyFuncPtr p) : m_p(p) {}

    constexpr ReturnType operator() (const T& val) const
    {
        return (val.*m_p)();
    }

private:

    MyFuncPtr m_p;
};

int main()
{
    {
        using Array = std::array<int, 3>;
        constexpr std::array<int, 3> a = { 1, 2, 3 };
        stateless<Array, a> s;
    }

    {
        constexpr A a = { 1 };
        stateless<A, a> s;
    }

    // All the code above compiles, but the code below does not.

    {
        using Getter = func_getter<A, int>;
        constexpr Getter g(&A::GetX);
        stateless<Getter, g> s;
    }

    {
        constexpr func_getter g(&A::GetX);
        stateless<decltype(g), g> s;
    }

    return 0;
}

字符串
MSVC 2022错误：

error C2993: 'Getter': is not a valid type for non-type template parameter 'state'

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