I wonder what is the lifetime of underlying storage referenced by std::span returned from such functions as std::meta::members_of? Is this array persisted throughout the compilation process?

Another question is why s_members.size() == 7 in the example on page 35? Why members_of(^S) include generated constructors and the destructor, but don't include generated assignment operators?

If i understand correctly std::meta::parameters_of could return function parameters or template parameters depending on the argument, and so for the following function template:

template<typename X, typename Y>

void f(X a, Y b);

parameters_of(^f) == {^X, ^Y};

parameters_of(^f(1, 2)) == {^a, ^b};

And likewise for generic lambda

auto lambda = []<typename X, typename Y>(X a, Y b) {};

parameters_of(^decltype(lambda)) == {^X, ^Y};

parameters_of(^lambda(1, 2)) = {^a, ^b};

Maybe it makes sense to split function `parameters_of` to 2 separate functions `function_parameters_of` and `template_paramters_of`?

On Sat, Jan 15, 2022 at 8:41 PM Daveed Vandevoorde via SG7 <sg7@lists.isocpp.org> wrote:

Hello reflecting friends,

(And Happy New Year!)

I’ve uploaded on the 2022 Teleconferences wiki for SG-7 an updated version of P1240 (which has also been submitted for the next mailing).

Changes include:

— The syntax agreements that SG-7 voted through P2320 (e.g., prefix ^ instead of reflexpr(…) to create reflections)

— The proposed metafunctions now use span and string_view instead of vector and string

— Various corrections and clarifications based on reader feedback and implementation experience

Daveed

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