Re: [review][fixed_string] End of review periodapproaching and a plea

From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2019-12-04 23:50:10

On 2019-12-05 02:43, Peter Dimov via Boost wrote:
> Andrey Semashev wrote:
> 
>> I think, fixed_string<0> should be specialized to an empty class. Not 
>> that I have a specific use case for fixed_string<0>, but making the 
>> class empty in general is useful for EBO and [[non_unique_address]] 
>> and e.g. tuples that employ these techniques.
> 
> Since values of the same type can't have the same address, you'll be 
> gaining at most one byte per tuple even if you put 1089 fixed_string<0>s 
> in it.

Is it so? I thought [[non_unique_address]] was supposed to allow that.

> Although I suppose tuple<unsigned long, fixed_string<0>> can be 8 bytes 
> instead of 16.

If such a tuple is e.g. bound into std::function, this may mean a 
difference between embedded storage and dynamic memory allocation.