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Re: Question about name lookup and class member?

From: Johannes Schaub <schaub.johannes_at_[hidden]>
Date: Mon, 7 Jun 2021 09:36:16 +0200
(sorry, sent again because I missed the ML first). Nice! Would this cause
comparable ambiguity in the case of NSDMI?

bool x = f<55, z = 66>(y);

Edward Catmur <ecatmur_at_[hidden]> schrieb am So., 6. Juni 2021, 21:40:

> 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?
>>> --
>>> Std-Discussion mailing list
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>>>
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>

Received on 2021-06-07 02:36:29