struct FlatHashMap(K, V = void, alias hasher = hashOf, string keyEqualPred = defaultKeyEqualPredOf!(K), Allocator = Mallocator, bool borrowChecked = false, bool useSmallLinearSearch = true, bool usePrimeCapacity = false)
enum hasAddressLikeKey =
(isAddress!K || isSlice!K);
Is true iff K is an address, in which case holes are represented by a specific value holeKeyConstant.