I’m not sure they’re trivial to deal with, at least in a way that could be
standardized. While it's defined source code lives in files, the concept of
a path/filesystem is not defined outside the stdlib. Maybe this could be
worded along the lines of if a filesystem exists, #pragma once behaves as
if by std::filesystem::equivalent, otherwise implementation defined. But
"filesystem" would need to be defined.

Jeremy

On Thu, Aug 29, 2024 at 17:25 Jonathan Wakely via Std-Proposals <
std-proposals_at_[hidden]> wrote:

>
>
> On Tue, 27 Aug 2024, 17:47 Tiago Freire via Std-Proposals, <
> std-proposals_at_[hidden]> wrote:
>
>> I agree that pragma once should mean same file and not file with same
>> bits.
>>
>> But I disagree on everything else.
>> I used pragma once exclusively on all my libraries quite successfully,
>> they are well organized and no such confusion could occur by design, "as a
>> well orchestrated build should".
>>
>> If you are in a situation where this causes problems, either by having
>> multiple copies of the same library or by using symbolic or hard links,
>> and they all end up on the same include stack. Well... then don't do that
>> then! Seems like a you problem.
>>
>
> More than once you've talked about problems caused by hard links and
> symbolic links being user error. That makes me think your don't actually
> understand the issues, because hard links and symbolic links are trivial to
> deal with here. Those aren't the problems people are worried about.
>
>
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