On Thu, Jun 29, 2023 at 12:05 AM Ville Voutilainen via Std-Proposals
<std-proposals_at_[hidden]> wrote:
>>
> > Indeed. This is boost::synchronized_value<T>.
>
> There's also a synchronized_value in
> https://open-std.org/JTC1/SC22/WG21/docs/papers/2023/n4953.pdf
> I thought Jonathan mentioned that earlier?


It turns out that the GNU compiler g++ version 13 already has this
under std::experimental.

Looking through the implementation of boost:synchronized_value, it
looks like it uses a regular mutex. My own implementation of my own
class uses a recursive mutex so that you can do stuff like:

void Func2(void)
{
    g_obj->push_back(78);
}

void Func(void)
{
    auto mylock = g_obj.Reserve();
    mylock->push_back(73);
    mylock->push_back(71);
    Func2(); // This would cause thread-lock if the mutex weren't a
recursive_mutex
    mylock->push_back(79);
}

I think a recursive_mutex is better here.