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Re: [std-proposals] requires keyword (new use)

From: Abdullah Qasim <iamminecraftredstoner_at_[hidden]>
Date: Tue, 3 May 2022 06:41:46 +0000
Any idea how I can implement some keywords?
So that I can test them out too?

P. S. Sorry about so many suggestions; I had these for weeks, & only recently figured out tha std-proposals is for features other thatn library ones too.

From: Jason McKesson via Std-Proposals<mailto:std-proposals_at_[hidden]>
Sent: 01 May 2022 22:00
To: std-proposals_at_[hidden]<mailto:std-proposals_at_[hidden]>
Cc: Jason McKesson<mailto:jmckesson_at_[hidden]>
Subject: Re: [std-proposals] requires keyword (new use)

On Sun, May 1, 2022 at 4:15 AM Abdullah Qasim via Std-Proposals
<std-proposals_at_[hidden]> wrote:
> int menu (/**/requires/**/ unsigned int menu_option = 0)
> // Called as:
> menu(default);
> // OR:
> menu(5)
> // Compiler Error: function "menu(unsigned int)" requires //unsigned int variable
> menu()
> I do not want calls like menu(), but I do want ability to call menu(default), as, in this case, going to default screen makes perfect sense.

So, you don't want the purpose of default parameters (ie: being able
to not provide an argument for that parameter), but you want certain
effects of default parameters (ie: having the function decide what the
parameter is).

So just take an `optional`:

int menu (std::optional<unsigned int> menu_option)
  if(!menu_option) menu_option = 0;
menu(); //Does not work.

Also, please don't spam the list with dozens of "proposals" like this.
We would like proposals to be more considered than "here's an idea I
had". C++ is a rich and varied language with many tools. You need to
take time to understand what those tools are and how to use them
*before* you can effectively start suggesting what tools the language
ought to have.
Std-Proposals mailing list

Received on 2022-05-03 06:41:47