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  3. TSortedMap

TSortedMap

A Map of keys to value, implemented as a sorted [TArray](API\Runtime\Core\Containers\TArray) of TPairs.

Unreal Engine C++ API Reference > Runtime > Core > Containers

Inheritance Hierarchy

References

   
Module Core
Header /Engine/Source/Runtime/Core/Public/Containers/SortedMap.h
Include #include "Containers/SortedMap.h"

Syntax

template<typename InKeyType, typename InValueType, typename ArrayAllocator, typename SortPredicate>  
class TSortedMap

Remarks

A Map of keys to value, implemented as a sorted TArray of TPairs.

It has a mostly identical interface to TMap and is designed as a drop in replacement. Keys must be unique, there is no equivalent sorted version of TMultiMap. It uses half as much memory as TMap, but adding and removing elements is O(n), and finding is O(Log n). In practice it is faster than TMap for low element counts, and slower as n increases, This map is always kept sorted by the key type so cannot be sorted manually.

Constructors

  Type Name Description
Public function    
Public function    
Public function  

TSortedMap ( const TSortedMap&
)

  
Public function  

TSortedMap ( TSortedMap< KeyType, ValueType, OtherArrayAllocator, SortPredicate >&& Other
)

 Constructor for moving elements from a TSortedMap with a different ArrayAllocator.
Public function  

TSortedMap ( const TSortedMap< KeyType, ValueType, OtherArrayAllocator, SortPredicate >& Other
)

 Constructor for copying elements from a TSortedMap with a different ArrayAllocator.
Public function  

TSortedMap ( std::initializer_list< TPairInitializer< const KeyType&, const ValueType& >> InitList
)

 Constructor which gets its elements from a native initializer list

Functions

  Type Name Description
Public function ValueType &

Add ( KeyType&& InKey,
const ValueType& InValue
)

  
Public function ValueType &

Add ( KeyType&& InKey,
ValueType&& InValue
)

  
Public function ValueType &

Add ( const KeyType& InKey,
ValueType&& InValue
)

  
Public function ValueType &

Add ( const KeyType& InKey,
const ValueType& InValue
)

 Sets the value associated with a key.
Public function ValueType &

Add ( KeyType&& InKey
)

  
Public function ValueType &

Add ( const KeyType& InKey
)

 Sets a default value associated with a key.
Public function void

Append ( const TSortedMap< KeyType, ValueType, OtherArrayAllocator, OtherSortPredicate >& OtherMap
)

 Add all items from another map to our map (if any keys are in both, the value from the other map wins).
Public function void

Append ( TSortedMap< KeyType, ValueType, OtherArrayAllocator, OtherSortPredicate >&& OtherMap
)

 Move all items from another map into our map (if any keys are in both, the value from the other map wins) and empty the other map.
Public function Const RangedForConstIteratorType

begin ()

  
Public function RangedForIteratorType

begin ()

 DO NOT USE DIRECTLY STL-like iterators to enable range-based for loop support.
Public function Const bool Checks if map contains the specified key.
Public function Const void Tracks the container's memory use through an archive.
Public function Const TConstIterator Creates a const iterator over all the pairs in this map
Public function Const TConstKeyIterator Creates a const iterator over the values associated with a specified key in a map.
Public function TIterator Creates an iterator over all the pairs in this map
Public function TKeyIterator Creates an iterator over the values associated with a specified key in a map.
Public function void Describes the map's contents through an output device.
Public function ValueType &

Emplace ( InitKeyType&& InKey
)

 Sets a default value associated with a key.
Public function ValueType &

Emplace ( InitKeyType&& InKey,
InitValueType&& InValue
)

 Sets the value associated with a key.
Public function void

Empty ( int32 ExpectedNumElements
)

 Removes all elements from the map, potentially leaving space allocated for an expected number of elements about to be added.
Public function Const RangedForConstIteratorType

end ()

  
Public function RangedForIteratorType

end ()

  
Public function Const const ValueType *  
Public function ValueType * Returns the value associated with a specified key.
Public function ValueType Finds a pair with the specified key, removes it from the map, and returns the value part of the pair.
Public function Const const ValueType &  
Public function ValueType & Returns a reference to the value associated with a specified key.
Public function Const const KeyType * Returns the key associated with the specified value. The time taken is O(N) in the number of pairs.
Public function ValueType &

FindOrAdd ( const KeyType& Key
)

 Returns the value associated with a specified key, or if none exists, adds a value using the default constructor.
Public function ValueType &

FindOrAdd ( KeyType&& Key
)

  
Public function Const ValueType Returns the value associated with a specified key.
Public function Const void

GenerateKeyArray ( TArray< KeyType, Allocator >& OutArray
)

 Generates an array from the keys in this map.
Public function Const void

GenerateValueArray ( TArray< ValueType, Allocator >& OutArray
)

 Generates an array from the values in this map.
Public function ElementType & Return a mapped pair by internal identifier. Element must be valid (see ).
Public function Const const ElementType & Return a mapped pair by internal identifier. Element must be valid (see ).
Public function Const SIZE_T Helper function to return the amount of memory allocated by this container.
Public function Const int32

GetKeys ( TArray< KeyType, Allocator >& OutKeys
)

 Returns the unique keys contained within this map.
Public function Const int32  
Public function Const bool

IsEmpty ()

 Returns true if the map is empty and contains no elements.
Public function Const bool Checks whether an element id is valid.
Public function Const int32

Num ()

  
Public function int32 Removes all value associations for a key.
Public function bool

RemoveAndCopyValue ( KeyInitType Key,
ValueType& OutRemovedValue
)

 Removes the pair with the specified key and copies the value that was removed to the ref parameter.
Public function void

Reserve ( int32 Number
)

 Preallocates enough memory to contain Number elements.
Public function void

Reset ()

 Efficiently empties out the map but preserves all allocations and capacities.
Public function void

Shrink ()

 Shrinks the pair set to avoid slack.

Operators

  Type Name Description
Public function Const bool

operator!= ( const TSortedMap& Other
)

 Inequality operator. This is efficient because pairs are always sorted.
Public function ValueType &  
Public function Const const ValueType &  
Public function TSortedMap &

operator= ( TSortedMap< KeyType, ValueType, OtherArrayAllocator, SortPredicate >&& Other
)

 Assignment operator for moving elements from a TSortedMap with a different ArrayAllocator.
Public function TSortedMap &

operator= ( std::initializer_list< TPairInitializer< const KeyType&, const ValueType& >> InitList
)

 Assignment operator which gets its elements from a native initializer list
Public function TSortedMap &  
Public function TSortedMap &

operator= ( const TSortedMap&
)

  
Public function TSortedMap &

operator= ( const TSortedMap< KeyType, ValueType, OtherArrayAllocator, SortPredicate >& Other
)

 Assignment operator for copying elements from a TSortedMap with a different ArrayAllocator.
Public function Const bool

operator== ( const TSortedMap& Other
)

 Equality operator. This is efficient because pairs are always sorted.

Classes

  Type Name Description
Public class TConstIterator Const map iterator  
Public class TConstKeyIterator Iterates over values associated with a specified key in a const map.  
Public class TConstReverseIterator Const map iterator  
Public class TIterator Map iterator  
Public class TKeyIterator Iterates over values associated with a specified key in a map.  
Public class TReverseIterator Reverse Map iterator  

Typedefs

Name Description
ElementArrayType  
ElementType  
KeyConstPointerType  
KeyInitType  
KeyType  
RangedForConstIteratorType  
RangedForIteratorType Ranged For iterators.
ValueInitType  
ValueType  

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