On Fri, Jun 16, 2023 at 5:43 AM Barry Revzin via Core <core_at_[hidden]>
wrote:

> While I'm not sure it's a great idea to #define _, I think we should
> generally err on the side of providing macros for features than not - since
> we've missed a few over the years in ways that have mattered.
>
> Looks like the latest revision of the paper has one already.
>
> Thanks!
>


I would like to bikeshed the name, it should be __cpp__



Barry
>
> On Thu, Jun 15, 2023 at 12:33 AM Corentin via Core <core_at_[hidden]>
> wrote:
>
>> + SG10
>> This pattern is principally used for global variables, for which
>> placeholders are not allowed, so I doubt this would be useful.
>> That being said, I defer to SG10 call, I'm happy to add one if
>> people think it would have use cases.
>>
>> Thanks!
>>
>>
>>
>>
>>
>>
>>
>> On Wed, Jun 14, 2023 at 10:33 PM Christof Meerwald <cmeerw_at_[hidden]>
>> wrote:
>>
>>> Not sure how widespread these workarounds are, but there are
>>> stackoverflow questions related to this:
>>>
>>>
>>> https://stackoverflow.com/questions/10379691/creating-macro-using-line-for-different-variable-names
>>>
>>> https://stackoverflow.com/questions/1082192/how-to-generate-random-variable-names-in-c-using-macros
>>> https://stackoverflow.com/questions/461062/c-anonymous-variables
>>>
>>> (and I think I have seen real-world code using these workarounds)
>>>
>>> So I think the use case for a feature-test macro would be something
>>> like this:
>>>
>>> #ifndef __unnamed_placeholder
>>> #define CONCAT2(a, b) a ## b
>>> #define CONCAT(a, b) CONCAT2(a, b)
>>> #ifdef __COUNTER__
>>> #define _ CONCAT(placeholder, __COUNTER__)
>>> #else
>>> #define _ CONCAT(placeholder, __LINE__)
>>> #endif
>>> #endif
>>>
>>> void f()
>>> {
>>> int _ = 1;
>>> int _ = 2;
>>> }
>>>
>>>
>>> Christof
>>>
>>> --
>>>
>>> https://cmeerw.org sip:cmeerw at cmeerw.org
>>> mailto:cmeerw at cmeerw.org xmpp:cmeerw at cmeerw.org
>>>
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