Hi,

What breaks by making tuple an aggregate? Would it affect ABI?

There was a good point about EBO, and I think neither `Ts... ts;` nor `[[no_unique_address]] Ts... ts;` would produce the same layout as current tuple implementations, at least on Itanium. AFAIK current implementations do make use of EBO, but they don't overlap non-empty tuple members on tail padding, while [[no_unique_address]] would do that.

Maybe it could be worked around with `[[no_unique_address]] wrapper<Ts>... ts;`, but then initialization with brace-elision can become awkward (see std::array).

Cheers,
Lénárd

On 7 June 2022 20:27:45 BST, Jason McKesson via Std-Proposals <std-proposals@lists.isocpp.org> wrote:

There's one thought that immediately comes to mind: even if we can
make parameter pack members like you want... you can't change how
`std::tuple` works. It is going to have to be given a different name.
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