Yes, i've heard this feedback before. I'm very much open to alternatives. [[requires no_unique_address]] is one i toyed with, but it is rather verbose. A non-alphanumeric syntax also has the benefit of not being even close to valid with an attribute-specifier in C++20.



On 4 May 2023, 11:29, at 11:29, Bo Persson via Std-Proposals <std-proposals_at_[hidden]> wrote:
>On 2023-05-04 at 09:47, Lauri Vasama via Std-Proposals wrote:
>> Floating an idea i've been toying around with for a while concerning
>a
>> new syntax for attributes with observable effects on program
>behaviour.
>>
>> https://vasama.github.io/wg21/Dxxx1
><https://vasama.github.io/wg21/Dxxx1>
>>
>>
>
>Don't see that an exclamation mark is a good choice for "required", as
>it elsewhere means "not".
>
>Like [[packed]] is optional, but [[!packed]] should be required
>packing.
>To me it look more like unpacked.
>
>
>
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