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Searching for "#define unless" AND (language:C++ OR language:C) on GitHub

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#define unless(COND) if (!(COND))

--
Zhihao Yuan, ID lichray
The best way to predict the future is to invent it.
_______________________________________________
On Saturday, April 20th, 2024 at 1:18 PM, Andrew Tomazos via Std-Proposals <std-proposals_at_[hidden]> wrote:
> No, I said that `unless` is claimable as a full keyword. It means it occurs so infrequently in existing code that the committee would accept it as a new keyword, even though it might break a tiny amount of uses of the identifier `unless`, because there are so few in the field.
> -Andrew
> 
> On Sun, Apr 21, 2024 at 6:08 AM Yexuan Xiao <bizwen_at_[hidden]> wrote:
> 
> > Thank you for your encouragement. Introducing a new keyword would be a breaking change, so I’m leaning towards a compromise solution. The use of if ! or if not should suffice. I’ve just analyzed the Rails codebase, and the usage of unless is nearly one-fifth that of if. So, while the issues it addresses aren’t as frequent, it can still be widely used.
> > 
> > 
> > From: Andrew Tomazos <andrewtomazos_at_[hidden]>
> > Sent: Sunday, April 21, 2024 3:53
> > To: std-proposals_at_[hidden] <std-proposals_at_[hidden]>
> > Cc: Yexuan Xiao <bizwen_at_[hidden]>
> > Subject: Re: [std-proposals] if !(condition)
> > 
> > * In my estimation `unless` is claimable as a full keyword:
> > 
> > unless (is_pickle())
> > put_in_sandwidch();
> > 
> > (There is existing practice in another language, can't remember which one.)
> > 
> > * It's hard to believe, but: `if (!expr)` occurs once in every 60 lines of C++ code, or about 5 times per source file.
> > 
> > That's pretty amazing, I would never have guessed that.
> > 
> > * You are correct that `while(!expr)` is much rarer. Only 1 in every 5000 lines or so.
> > 
> > * You are also correct that `operator!` overloading is almost non-existent.
> > 
> > -Andrew
> > 
> > 
> > 
> > 
> > On Sun, Apr 21, 2024 at 3:34 AM Yexuan Xiao via Std-Proposals <std-proposals_at_[hidden]> wrote:
> > 
> > > Firstly, I believe that this particular case in if statements is the most common, so it’s my main focus; secondly, the ‘if not’ construct already exists and is widely used elsewhere, making it more readily acceptable. Therefore, the proposal will focus exclusively on if statements rather than loop statements.
> > > 
> > > From: Std-Proposals <std-proposals-bounces_at_[hidden]> on behalf of Sebastian Wittmeier via Std-Proposals <std-proposals_at_[hidden]>
> > > Sent: Sunday, April 21, 2024 1:18
> > > To: std-proposals_at_[hidden] <std-proposals_at_[hidden]>
> > > Cc: Sebastian Wittmeier <wittmeier_at_[hidden]>
> > > Subject: Re: [std-proposals] if !(condition)
> > > 
> > > I would expect a comment about "while" and "do while" (and possibly "for").
> > > 
> > > Would you propose adding ! there, too, oppose it, leave it neutrally open, invite anybody to write a paper or want to see, how if !() works out? Or is it not possible there?
> > > 
> > > 
> > > 
> > > > -----Ursprüngliche Nachricht-----
> > > > Von: Yexuan Xiao via Std-Proposals <std-proposals_at_[hidden]>
> > > > Gesendet: Sa 20.04.2024 18:09
> > > > Betreff: [std-proposals] if !(condition)
> > > > An: std-proposals_at_[hidden] <Std-Proposals_at_[hidden]>;
> > > > CC: Yexuan Xiao <bizwen_at_[hidden]>;
> > > > I've wrote a proposal that suggests allowing the omission of the outermost parentheses to simplify the conditions in if statements:
> > > > https://storage.nykz.org/proposals/if-not/
> > > > 
> > > > Please share your comments.
> > > > 
> > > > --
> > > >  Std-Proposals mailing list
> > > >  Std-Proposals_at_[hidden]
> > > >  https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals
> > > >  
> > > 
> > > --
> > > Std-Proposals mailing list
> > > Std-Proposals_at_[hidden]
> > > https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals