Does using contents for #pragma once break any practical or plausible uses
of #pragma once? Does it have any clear downsides?

I don’t think does. It should only make things more robust and portable.

Jeremy

On Tue, Aug 27, 2024 at 12:07 Andrey Semashev via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On 8/27/24 17:01, Jeremy Rifkin via Std-Proposals wrote:
> > Hi,
> > I have drafted a proposal for standardizing #pragma once. This has been
> > previously proposed a few years ago and I recognize that on top of being
> > difficult to standardize, existing opinions on this topic may render the
> > paper dead on arrival. However, due to its widespread nature and
> > concerns about portability contributing to it not being used more I
> > think it's worth revisiting. I have uploaded the first draft at:
> >
> https://jeremy-rifkin.github.io/cpp-proposals/drafts/pragma-once-draft-1.html
> <
> https://jeremy-rifkin.github.io/cpp-proposals/drafts/pragma-once-draft-1.html
> >.
>
> I think, using file contents for `#pragma once` is wrong and should not
> be standardized. The intended effect of `#pragma once` has always been
> to avoid including *the same header* twice, not *the same content*.
>
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