AK: Allow testing Empty instances for equality

This also makes it possible to compare `Variant<Empty, Ts...>` objects if operator== exists for all Ts
Author: https://github.com/shannonbooth Commit: bf7af25a82 Pull-request: https://github.com/SerenityOS/serenity/pull/20219 Reviewed-by: https://github.com/Hendiadyoin1 Reviewed-by: https://github.com/alimpfard Reviewed-by: https://github.com/gmta
2025-08-31 06:38:22 +00:00 · 2023-07-27 22:14:56 +12:00 · 2023-07-27 22:14:56 +12:00 · bf7af25a82 · 2024-07-16 23:34:49 +09:00
commit bf7af25a82
parent 4f9f21e8fe
2 changed files with 30 additions and 0 deletions
--- a/AK/Variant.h
+++ b/AK/Variant.h
@ -217,6 +217,7 @@ using MergeAndDeduplicatePacks = InheritFromPacks<MakeIndexSequence<sizeof...(Ps
 namespace AK {

 struct Empty {
+    constexpr bool operator==(Empty const&) const = default;
 };

 template<typename T>