22 using std::optional;
72     using std::optional;  in test_swap_sfinae()
75         static_assert(std::is_swappable_v<optional<T>>, "");  in test_swap_sfinae()
79         static_assert(std::is_swappable_v<optional<T>>, "");  in test_swap_sfinae()
83         static_assert(std::is_swappable_v<optional<T>>, "");  in test_swap_sfinae()
87         static_assert(!std::is_swappable_v<optional<T>>, "");  in test_swap_sfinae()
91         static_assert(!std::is_swappable_v<optional<T>>, "");  in test_swap_sfinae()
98         using Opt = optional<T>;  in test_swap_sfinae()
116         optional<int> opt1;  in main()
117         optional<int> opt2;  in main()
126         optional<int> opt1(1);  in main()
127         optional<int> opt2;  in main()
138         optional<int> opt1;  in main()
139         optional<int> opt2(2);  in main()
150         optional<int> opt1(1);  in main()
151         optional<int> opt2(2);  in main()
164         optional<X> opt1;  in main()
165         optional<X> opt2;  in main()
175         optional<X> opt1(1);  in main()
176         optional<X> opt2;  in main()
189         optional<X> opt1;  in main()
190         optional<X> opt2(2);  in main()
203         optional<X> opt1(1);  in main()
204         optional<X> opt2(2);  in main()
219         optional<Y> opt1;  in main()
220         optional<Y> opt2;  in main()
230         optional<Y> opt1(1);  in main()
231         optional<Y> opt2;  in main()
244         optional<Y> opt1;  in main()
245         optional<Y> opt2(2);  in main()
258         optional<Y> opt1(1);  in main()
259         optional<Y> opt2(2);  in main()
274         optional<Z> opt1;  in main()
275         optional<Z> opt2;  in main()
285         optional<Z> opt1;  in main()
287         optional<Z> opt2;  in main()
306         optional<Z> opt1;  in main()
307         optional<Z> opt2;  in main()
327         optional<Z> opt1;  in main()
329         optional<Z> opt2;  in main()