| 257 | ////////////////////////////////////////////////////////////////////////////// |
| 258 | template <typename Sequence> |
| 259 | struct copy { |
| 260 | using type = decltype(hana::to_tuple(Sequence{})); |
| 261 | }; |
| 262 | |
| 263 | template <typename Sequence, typename Pred> |
| 264 | struct copy_if { |