PREPROCESSOR_JOIN

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Overloads

PREPROCESSOR_JOIN(UE_TMAP_PREFIX, MapBase)

Description

The base class of maps from keys to values. Implemented using a TSet of key-value pairs with a custom KeyFuncs, with the same O(1) addition, removal, and finding.

The ByHash() functions are somewhat dangerous but particularly useful in two scenarios: Heterogeneous lookup to avoid creating expensive keys like FString when looking up by const TCHAR*. You must ensure the hash is calculated in the same way as ElementType is hashed. If possible put both ComparableKey and ElementType hash functions next to each other in the same header to avoid bugs when the ElementType hash function is changed. Reducing contention around hash tables protected by a lock. It is often important to incur the cache misses of reading key data and doing the hashing before acquiring the lock.

template<typename KeyType, typename ValueType, typename SetAllocator, typename KeyFuncs>  
class PREPROCESSOR_JOIN  
(  
    UE_TMAP_PREFIX,  
    MapBase  
)  
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template<typename KeyType, typename ValueType, typename SetAllocator, typename KeyFuncs> class PREPROCESSOR_JOIN (     UE_TMAP_PREFIX,     MapBase )

PREPROCESSOR_JOIN(PREPROCESSOR_JOIN(UE_TMAP_PREFIX, Map), PrivateFriend)

struct PREPROCESSOR_JOIN  
(  
    PREPROCESSOR_JOIN),  
    PrivateFriend  
)  
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struct PREPROCESSOR_JOIN (     PREPROCESSOR_JOIN),     PrivateFriend )