Initial support for TMap properties was added recently: https://github.com/EpicGames/UnrealEngine/commit/7147a13be21a7a05b502d649f5baf027b851dcf7
This should be regarded as WIP, but it currently supports reflection, text conversion, garbage collection and delta serialisation.
Editor support is basic - currently maps just show up as text edit fields - but we’re hoping to improve on that in the near future:
UPROPERTY(EditAnywhere, Category=TestMap)
TMap<int32, FString> LetsSeeIfThisWorks;
LetsSeeIfThisWorks.Add(0, "Test: 1");
LetsSeeIfThisWorks.Add(1, "Test: 3");
No blueprint support yet.
Steve