On Tuesday, November 3, 2020 10:01 PM, D'Alessandro, Luke K via Std-Proposals <std-proposals@lists.isocpp.org> wrote:

template <typename T>

constexpr array<T, 0> to_array(std::array<T, 0>);

I see no particular constraints on T in [array.zero], nor do any of the constructor traits appear to be relevant here, thus I have no preconditions and merely carried forward the is_array_v mandate from the existing overloads.

Since you get rationale and examples,

that fits in a small paper.

I slightly prefer a tag solution, because

array<T, 0> is not physically zero (or 1) size.

Accepting one as an argument may have

some cost. Another issue is that the type

array<T, 0> is public. You don't mean to

allow people to do

std::array<int, 0> a;

foo(to_array(a));

Zhihao Yuan, ID lichray
The best way to predict the future is to invent it.
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