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Subject: Re: Question about name lookup and class member?
From: Edward Catmur (ecatmur_at_[hidden])
Date: 2021-06-06 14:40:23


On Sun, 6 Jun 2021 at 19:54, Johannes Schaub via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> This is an item in issue
> http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#325 . A
> couple of community members created an openoffice document during C++11
> last-minute-fixes and this was on that list.
>

Hm, here's a fun one:

struct C {
    C(bool);
    constexpr C(int) {}
    constexpr C& operator=(int)&& { return *this; }
    constexpr operator int() const { return 22; }
};
static constexpr int x = 33;
static constexpr int y = 44;
struct A {
    template<int, int> static bool f(int);
    //static constexpr int f = 77;
    int g(bool = f<55, C(x) = 66>(y));
};
int i = A().g();

MSVC and icc accept (with A::g a function of 1 argument); gcc and clang
reject. If f is changed to the non-template static data member (s.t. A::g
is now a function of 2 arguments), everyone accepts.

If f as a static member function template is moved to after g, all reject;
if it is a non-template static data member all except icc accept.

Eric Suen via Std-Discussion <std-discussion_at_[hidden]> schrieb am
> So., 6. Juni 2021, 20:16:
>
>> >
>> > NSDMIs are evaluated in a complete-class context. This is one reason
>> > they can't be `auto`.
>> >
>> How do you get complete-class context when you unable to parse
>>
>> int a = V<1>();
>>
>> correctly?
>>
>> Look ahead for ';' if you encounter '=' in declarator?
>> --
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>>
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