On 11/10/24 11:04, André Offringa via Std-Proposals wrote:

> I'd like to float the idea to make it possible to construct a
> std::complex and a std::vector uninitialized. Basically, I would propose
> something like the following to exist.

Another approach is to use a wrapper that leaves the enclosed value
uninitialized by default. You probably want to constrain such a wrapper
to only work for trivially destructible types.

With such a wrapper you can use:

   std::vector<uninitialized<char>> a;
   std::complex<uninitialized<double>> b;

This will work with other existing containers as well.

There was a proposal to add std::uninitialized, but that proposal has
morphed into something else:

   https:://wg21.link/P3074