But P2321R2 has made it legal.

On Friday, October 7, 2022, Oleksandr Koval <oleksandr.koval.dev_at_[hidden]>
wrote:
> Wow, that's super weird:
> std::vector<bool> v;
> const auto b = v[0];
> b = true; // o_0
>
> On Fri, Oct 7, 2022 at 3:40 PM blacktea hamburger via Std-Proposals <
std-proposals_at_[hidden]> wrote:
>>
>> But their name is "reference". Also, std::vector<bool>::reference has a
const assignment operator:
>>
>> constexpr const reference& operator=(bool x) const noexcept;
>>
>> On Fri, Oct 7, 2022 at 8:34 PM Oleksandr Koval <
oleksandr.koval.dev_at_[hidden]> wrote:
>>>
>>> I think the intent here is to mimic value semantics since assignment
actually changes referenced value. Making those functions `const` would be
confusing.
>>>
>>> On Fri, Oct 7, 2022 at 2:42 PM blacktea hamburger via Std-Proposals <
std-proposals_at_[hidden]> wrote:
>>>>
>>>> std::vector<bool>::reference and std::bitset::reference are both
proxies, so even if they themselves are const, they can still be used to
change the bit they reference.
>>>> Are there any issues?
>>>> --
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>>>> Std-Proposals_at_[hidden]
>>>> https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals
>>>
>>>
>>> --
>>> Regards,
>>> Oleksandr Koval.
>>
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>
>
> --
> Regards,
> Oleksandr Koval.
>