| // Pack expansion testcases from P2082R1 |
| // { dg-do compile { target c++20 } } |
| |
| template<typename U, typename... T> |
| struct C2 : T... { |
| U a; |
| static constexpr int len = sizeof...(T); |
| }; |
| C2 c2 = { |
| []{ return 1; }, |
| }; |
| static_assert (c2.len == 0); |
| |
| template <typename... T> |
| struct Types {}; |
| template <typename... T> |
| struct F : Types<T...>, T... {}; |
| struct X {}; |
| struct Y {}; |
| struct Z {}; |
| struct W { operator Y(); }; |
| F f1 = {Types<X, Y, Z>{}, {}, {}}; // OK, F<X, Y, Z> deduced |
| F f2 = {Types<X, Y, Z>{}, X{}, Y{}}; // OK, F<X, Y, Z> deduced |
| F f3 = {Types<X, Y, Z>{}, X{}, W{}}; // { dg-error "" } conflicting types deduced; operator Y not considered |
