Date: Tue, 14 Oct 2025 16:12:53 +0000
[Rene]
* Perhaps there's some method I don't know about.
Fair, not knowing (e.g. incertitude) is different from assertion of impossibility (certitude of the impossible), which made me think you had access to something else that I didn’t have, which is why I was asking for elaboration on your assertion so I could understand.
* So I'll ask you.
I didn’t claim I knew of the proof of the assertion that you made. Rather, I was asking to elaborate on your assertion so I could understand it. Turning the question around doesn’t achieve any of that. I would be content if your answer were “I don’t know”.
* Can you think of a way to guarantee the above is true?
For the interest of the conversation, I would confess upfront that I don’t know everything (unlike some among us in this august forum).
One way I know of protecting my macros from interference from the “outside” is to use #pragma push_macro, supported by GCC<https://gcc.gnu.org/onlinedocs/gcc/Push_002fPop-Macro-Pragmas.html>, Clang, and MSVC<https://learn.microsoft.com/en-us/cpp/preprocessor/push-macro?view=msvc-170>, to protect my macro definitions. Then interfering with it would require any of similar means as interfering with any other portion of the code that I author without macros. But, then again, I didn’t make the claim of the impossibility you made earlier.
-- Gaby
From: René Ferdinand Rivera Morell <grafikrobot_at_[hidden]>
Sent: Tuesday, October 14, 2025 11:41 AM
To: Gabriel Dos Reis <gdr_at_[hidden]>
Cc: sg15_at_[hidden]; SG21 - Contracts <sg21_at_[hidden]>; John Spicer <jhs_at_[hidden]>
Subject: Re: [isocpp-sg15] [isocpp-sg21] P3835 -- Different contract checking for different libraries
On Tue, Oct 14, 2025 at 10:09 AM Gabriel Dos Reis <gdr_at_[hidden]<mailto:gdr_at_[hidden]>> wrote:
I am not quite sure I see how the impossibility follows from that statement, though. Are there some other assumptions at play?
Perhaps there's some method I don't know about. So I'll ask you.. Given what John said:
> The reason for this is that if you currently use a macro like MY_LIB_ASSERT(x), then you have control over what it does, even when your header is used by someone else.
Can you think of a way to guarantee the above is true?
--
-- René Ferdinand Rivera Morell
-- Don't Assume Anything -- No Supongas Nada
-- Robot Dreams - http://robot-dreams.net<http://robot-dreams.net/>
* Perhaps there's some method I don't know about.
Fair, not knowing (e.g. incertitude) is different from assertion of impossibility (certitude of the impossible), which made me think you had access to something else that I didn’t have, which is why I was asking for elaboration on your assertion so I could understand.
* So I'll ask you.
I didn’t claim I knew of the proof of the assertion that you made. Rather, I was asking to elaborate on your assertion so I could understand it. Turning the question around doesn’t achieve any of that. I would be content if your answer were “I don’t know”.
* Can you think of a way to guarantee the above is true?
For the interest of the conversation, I would confess upfront that I don’t know everything (unlike some among us in this august forum).
One way I know of protecting my macros from interference from the “outside” is to use #pragma push_macro, supported by GCC<https://gcc.gnu.org/onlinedocs/gcc/Push_002fPop-Macro-Pragmas.html>, Clang, and MSVC<https://learn.microsoft.com/en-us/cpp/preprocessor/push-macro?view=msvc-170>, to protect my macro definitions. Then interfering with it would require any of similar means as interfering with any other portion of the code that I author without macros. But, then again, I didn’t make the claim of the impossibility you made earlier.
-- Gaby
From: René Ferdinand Rivera Morell <grafikrobot_at_[hidden]>
Sent: Tuesday, October 14, 2025 11:41 AM
To: Gabriel Dos Reis <gdr_at_[hidden]>
Cc: sg15_at_[hidden]; SG21 - Contracts <sg21_at_[hidden]>; John Spicer <jhs_at_[hidden]>
Subject: Re: [isocpp-sg15] [isocpp-sg21] P3835 -- Different contract checking for different libraries
On Tue, Oct 14, 2025 at 10:09 AM Gabriel Dos Reis <gdr_at_[hidden]<mailto:gdr_at_[hidden]>> wrote:
I am not quite sure I see how the impossibility follows from that statement, though. Are there some other assumptions at play?
Perhaps there's some method I don't know about. So I'll ask you.. Given what John said:
> The reason for this is that if you currently use a macro like MY_LIB_ASSERT(x), then you have control over what it does, even when your header is used by someone else.
Can you think of a way to guarantee the above is true?
--
-- René Ferdinand Rivera Morell
-- Don't Assume Anything -- No Supongas Nada
-- Robot Dreams - http://robot-dreams.net<http://robot-dreams.net/>
Received on 2025-10-14 16:13:00