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TArray

Templated dynamic array

API > API/Runtime > API/Runtime/Core > API/Runtime/Core/Containers

Inheritance Hierarchy

References

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

Syntax

template<typename InElementType, typename InAllocatorType>  
class TArray

Remarks

Templated dynamic array

A dynamically sized array of typed elements. Makes the assumption that your elements are relocate-able; i.e. that they can be transparently moved to new memory without a copy constructor. The main implication is that pointers to elements in the TArray may be invalidated by adding or removing other elements to the array. Removal of elements is O(N) and invalidates the indices of subsequent elements.

Caution: as noted below some methods are not safe for element types that require constructors.

Variables

  Type Name Description
Protected variable ElementAllocatorType AllocatorInstance  
Protected variable SizeType ArrayMax  
Protected variable SizeType ArrayNum  

Constructors

  Type Name Description
Public function  

TArray ()

 Constructor, initializes element number counters.
Public function  

TArray ( TArray< OtherElementType, AllocatorType >&& Other,
SizeType ExtraSlack
)

 Move constructor.
Public function  

TArray ( const TArrayView< OtherElementType, OtherSizeType >& Other
)

  
Public function  

TArray ( std::initializer_list< InElementType > InitList
)

 Initializer list constructor
Public function  

TArray ( const TArray< OtherElementType, OtherAllocator >& Other
)

 Copy constructor with changed allocator. Use the common routine to perform the copy.
Public function  

TArray ( const TArray& Other
)

 Copy constructor. Use the common routine to perform the copy.
Public function  

TArray ( TArray&& Other
)

 Move constructor.
Public function  

TArray ( TArray< OtherElementType, OtherAllocator >&& Other
)

 Move constructor.
Public function  

TArray ( const ElementType* Ptr,
SizeType Count
)

 Constructor from a raw array of elements.
Public function  

TArray ( const TArray& Other,
SizeType ExtraSlack
)

 Copy constructor. Use the common routine to perform the copy.

Destructors

  Type Name Description
Public function  

~TArray ()

 Destructor.

Functions

  Type Name Description
Public function SizeType

Add ( const ElementType& Item
)

 Adds a new item to the end of the array, possibly reallocating the whole array to fit.
Public function SizeType

Add ( ElementType&& Item
)

 Adds a new item to the end of the array, possibly reallocating the whole array to fit.
Public function ElementType &

Add_GetRef ( const ElementType& Item
)

 Adds a new item to the end of the array, possibly reallocating the whole array to fit.
Public function ElementType &

Add_GetRef ( ElementType&& Item
)

 Adds a new item to the end of the array, possibly reallocating the whole array to fit.
Public function SizeType Adds new items to the end of the array, possibly reallocating the whole array to fit.
Public function SizeType  
Public function ElementType & Add a new item to the end of the array, possibly reallocating the whole array to fit.
Public function SizeType  
Public function SizeType Adds a given number of uninitialized elements into the array.
Public function SizeType

AddUnique ( const ElementType& Item
)

 Adds unique element to array if it doesn't exist.
Public function SizeType

AddUnique ( ElementType&& Item
)

 Adds unique element to array if it doesn't exist.Move semantics version.
Public function SizeType Adds new items to the end of the array, possibly reallocating the whole array to fit.
Public function SizeType

AddZeroed ( SizeType Count
)

  
Public function ElementType & Adds a new item to the end of the array, possibly reallocating the whole array to fit.
Public function void

Append ( const TArray< OtherElementType, OtherAllocatorType >& Source
)

 Appends the specified array to this array.AllocatorType changing version.
Public function void

Append ( TArray< OtherElementType, OtherAllocator >&& Source
)

 Appends the specified array to this array.
Public function void

Append ( RangeType&& Source
)

 Appends the elements from a contiguous range to this array.
Public function void

Append ( std::initializer_list< ElementType > InitList
)

 Adds an initializer list of elements to the end of the TArray.
Public function void

Append ( const ElementType* Ptr,
SizeType Count
)

 Adds a raw array of elements to the end of the TArray.
Public function void

Append ( const typename TContainerElementTypeCompatibility< ElementType >::CopyFromOtherType* Ptr,
SizeType Count
)

 Adds a raw array of elements to the end of the TArray.
Public function Static void

AppendHash ( const FPlatformTypeLayoutParameters& LayoutParams,
FSHA1& Hasher
)

  
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 void

BulkSerialize ( FArchive& Ar,
bool bForcePerElementSerialization
)

 Bulk serialize array as a single memory blob when loading.
Public function Const void

CheckAddress ( const ElementType* Addr
)

 Checks that the specified address is not part of an element within the container.
Public function Const void Checks array invariants: if array size is greater than or equal to zero and less than or equal to the maximum.
Public function Const bool

Contains ( const ComparisonType& Item
)

 Checks if this array contains the element.
Public function Const bool

ContainsByPredicate ( Predicate Pred
)

 Checks if this array contains an element for which the predicate is true.
Public function Const void

CopyUnfrozen ( const FMemoryUnfreezeContent& Context,
void* Dst
)

  
Public function Const void Count bytes needed to serialize this array.
Public function Const TConstIterator Creates a const iterator for the contents of this array
Public function TIterator Creates an iterator for the contents of this array
Public function SizeType

Emplace ( ArgsType&&... Args
)

 Constructs a new item at the end of the array, possibly reallocating the whole array to fit.
Public function ElementType &

Emplace_GetRef ( ArgsType&&... Args
)

 Constructs a new item at the end of the array, possibly reallocating the whole array to fit.
Public function void

EmplaceAt ( SizeType Index,
ArgsType&&... Args
)

 Constructs a new item at a specified index, possibly reallocating the whole array to fit.
Public function ElementType &

EmplaceAt_GetRef ( SizeType Index,
ArgsType&&... Args
)

 Constructs a new item at a specified index, possibly reallocating the whole array to fit.
Public function void

Empty ( SizeType Slack
)

 Empties the array. It calls the destructors on held items if needed.
Public function Const RangedForConstIteratorType

end ()

  
Public function RangedForIteratorType

end ()

  
Public function Const TArray< ElementType >

FilterByPredicate ( Predicate Pred
)

 Filters the elements in the array based on a predicate functor.
Public function Const SizeType

Find ( const ElementType& Item
)

 Finds element within the array.
Public function Const bool

Find ( const ElementType& Item,
SizeType& Index
)

 Finds element within the array.
Public function Const const ElementType *

FindByKey ( const KeyType& Key
)

 Finds an item by key (assuming the ElementType overloads operator== for the comparison).
Public function ElementType *

FindByKey ( const KeyType& Key
)

 Finds an item by key (assuming the ElementType overloads operator== for the comparison).
Public function ElementType *

FindByPredicate ( Predicate Pred
)

 Finds an element which matches a predicate functor.
Public function Const const ElementType *

FindByPredicate ( Predicate Pred
)

 Finds an element which matches a predicate functor.
Public function Const bool

FindItemByClass ( SearchType** Item,
SizeType* ItemIndex,
SizeType StartIndex
)

 Searches for the first entry of the specified type, will only work with TArray.
Public function Const SizeType

FindLast ( const ElementType& Item
)

 Finds element within the array starting from the end.
Public function Const bool

FindLast ( const ElementType& Item,
SizeType& Index
)

 Finds element within the array starting from the end.
Public function Const SizeType

FindLastByPredicate ( Predicate Pred
)

 Searches the array for the last occurrence of an element which matches the specified predicate.
Public function Const SizeType

FindLastByPredicate ( Predicate Pred,
SizeType Count
)

 Searches an initial subrange of the array for the last occurrence of an element which matches the specified predicate.
Public function Const SIZE_T Helper function to return the amount of memory allocated by this container.
Public function Const const ElementAllocatorType &  
Public function ElementAllocatorType &  
Public function ElementType *

GetData ()

 Helper function for returning a typed pointer to the first array entry.
Public function Const const ElementType *

GetData ()

 Helper function for returning a typed pointer to the first array entry.
Public function Const SizeType Returns the amount of slack in this array in elements.
Public function Static constexpr uint32 Helper function returning the size of the inner type.
Public function void

Heapify ()

 Builds an implicit heap from the array.
Public function void

Heapify ( const PREDICATE_CLASS& Predicate
)

 Implicit heaps Builds an implicit heap from the array.
Public function void

HeapPop ( ElementType& OutItem,
const PREDICATE_CLASS& Predicate,
bool bAllowShrinking
)

 Removes the top element from the heap.
Public function void

HeapPop ( ElementType& OutItem,
bool bAllowShrinking
)

 Removes the top element from the heap.
Public function void

HeapPopDiscard ( bool bAllowShrinking
)

 Removes the top element from the heap.
Public function void

HeapPopDiscard ( const PREDICATE_CLASS& Predicate,
bool bAllowShrinking
)

 Removes the top element from the heap.
Public function SizeType

HeapPush ( ElementType&& InItem
)

 Adds a new element to the heap.
Public function SizeType

HeapPush ( const ElementType& InItem
)

 Adds a new element to the heap.
Public function SizeType

HeapPush ( ElementType&& InItem,
const PREDICATE_CLASS& Predicate
)

 Adds a new element to the heap.
Public function SizeType

HeapPush ( const ElementType& InItem,
const PREDICATE_CLASS& Predicate
)

 Adds a new element to the heap.
Public function void

HeapRemoveAt ( SizeType Index,
bool bAllowShrinking
)

 Removes an element from the heap.
Public function void

HeapRemoveAt ( SizeType Index,
const PREDICATE_CLASS& Predicate,
bool bAllowShrinking
)

 Removes an element from the heap.
Public function void Performs heap sort on the array.
Public function void

HeapSort ( const PREDICATE_CLASS& Predicate
)

 Performs heap sort on the array.
Public function Const const ElementType &

HeapTop ()

 Returns the top element from the heap (does not remove the element).Const version.
Public function ElementType &

HeapTop ()

 Returns the top element from the heap (does not remove the element).
Public function Const SizeType

IndexOfByKey ( const KeyType& Key
)

 Finds an item by key (assuming the ElementType overloads operator== for the comparison).
Public function Const SizeType

IndexOfByPredicate ( Predicate Pred
)

 Finds an item by predicate.
Public function void

Init ( const ElementType& Element,
SizeType Number
)

 Sets the size of the array, filling it with the given element.
Public function SizeType

Insert ( const TArray< ElementType, OtherAllocator >& Items,
const SizeType InIndex
)

 Inserts given elements into the array at given location.
Public function SizeType

Insert ( TArray< ElementType, OtherAllocator >&& Items,
const SizeType InIndex
)

 Inserts given elements into the array at given location.
Public function SizeType

Insert ( ElementType&& Item,
SizeType Index
)

 Inserts a given element into the array at given location. Move semantics version.
Public function SizeType

Insert ( const ElementType& Item,
SizeType Index
)

 Inserts a given element into the array at given location.
Public function SizeType

Insert ( const TArray< typename TContainerElementTypeCompatibility< ElementType >::CopyFromOtherType, OtherAl...,
const SizeType InIndex
)

 Inserts given elements into the array at given location. Compatible element type version.
Public function SizeType

Insert ( std::initializer_list< ElementType > InitList,
const SizeType InIndex
)

 Inserts given elements into the array at given location.
Public function SizeType

Insert ( TArray< typename TContainerElementTypeCompatibility< ElementType >::CopyFromOtherType, OtherAllocato...,
const SizeType InIndex
)

 Inserts given elements into the array at given location. Compatible element type version.
Public function SizeType

Insert ( const ElementType* Ptr,
SizeType Count,
SizeType Index
)

 Inserts a raw array of elements at a particular index in the TArray.
Public function ElementType &

Insert_GetRef ( const ElementType& Item,
SizeType Index
)

 Inserts a given element into the array at given location.
Public function ElementType &

Insert_GetRef ( ElementType&& Item,
SizeType Index
)

 Inserts a given element into the array at given location. Move semantics version.
Public function void Inserts a given number of default-constructed elements into the array at a given location.
Public function void

InsertDefaulted ( SizeType Index,
SizeType Count
)

  
Public function ElementType & Inserts a default-constructed element into the array at a given location.
Public function void Inserts a given number of uninitialized elements into the array at given location.
Public function void  
Public function void Inserts a given number of zeroed elements into the array at given location.
Public function void

InsertZeroed ( SizeType Index,
SizeType Count
)

  
Public function ElementType & Inserts a zeroed element into the array at given location.
Public function Const bool

IsEmpty ()

 Returns true if the array is empty and contains no elements.
Public function Const bool Tests if index is valid, i.e. greater than or equal to zero, and less than the number of elements in the array.
Public function ElementType &

Last ( SizeType IndexFromTheEnd
)

 Returns n-th last element from the array.
Public function Const const ElementType &

Last ( SizeType IndexFromTheEnd
)

 Returns n-th last element from the array.Const version of the above.
Public function Const SizeType

Max ()

 Returns maximum number of elements in array.
Public function Const SizeType

Num ()

 Returns number of elements in array.
Public function TEnableIfTIsAbstract< ET >::Value, ElementType >::Type

Pop ( bool bAllowShrinking
)

 Pops element from the array.
Public function void

Push ( ElementType&& Item
)

 Pushes element into the array.
Public function void

Push ( const ElementType& Item
)

 Pushes element into the array.Const ref version of the above.
Public function Const void

RangeCheck ( SizeType Index
)

 Checks if index is in array range.
Public function RangedForReverseIteratorType

rbegin ()

  
Public function Const RangedForConstReverseIteratorType

rbegin ()

  
Public function SizeType

Remove ( const ElementType& Item
)

 Removes as many instances of Item as there are in the array, maintaining order but not indices.
Public function SizeType

RemoveAll ( const PREDICATE_CLASS& Predicate
)

 Remove all instances that match the predicate, maintaining order but not indices Optimized to work with runs of matches/non-matches
Public function SizeType

RemoveAllSwap ( const PREDICATE_CLASS& Predicate,
bool bAllowShrinking
)

 Remove all instances that match the predicate
Public function void

RemoveAt ( SizeType Index
)

 Removes an element (or elements) at given location, then shrinks the array.
Public function void

RemoveAt ( SizeType Index,
CountType Count,
bool bAllowShrinking
)

 Removes an element (or elements) at given location, optionally shrinking the array.
Public function void

RemoveAtSwap ( SizeType Index,
CountType Count,
bool bAllowShrinking
)

 Removes an element (or elements) at given location, optionally shrinking the array.
Public function void Removes an element (or elements) at given location, then shrinks the array.
Public function SizeType

RemoveSingle ( const ElementType& Item
)

 Removes the first occurrence of the specified item in the array, maintaining order but not indices.
Public function SizeType

RemoveSingleSwap ( const ElementType& Item,
bool bAllowShrinking
)

 Removes the first occurrence of the specified item in the array.
Public function SizeType

RemoveSwap ( const ElementType& Item,
bool bAllowShrinking
)

 Removes item from the array.
Public function Const RangedForConstReverseIteratorType

rend ()

  
Public function RangedForReverseIteratorType

rend ()

  
Public function void

Reserve ( SizeType Number
)

 Reserves memory such that the array can contain at least Number elements.
Public function void

Reset ( SizeType NewSize
)

 Same as empty, but doesn't change memory allocations, unless the new size is larger than the current array.
Public function void

SetNum ( SizeType NewNum,
bool bAllowShrinking
)

 Resizes array to given number of elements.
Public function void

SetNumUninitialized ( SizeType NewNum,
bool bAllowShrinking
)

 Resizes array to given number of elements. New elements will be uninitialized.
Public function void Does nothing except setting the new number of elements in the array.
Public function void

SetNumZeroed ( SizeType NewNum,
bool bAllowShrinking
)

 Resizes array to given number of elements, optionally shrinking it. New elements will be zeroed.
Public function void

Shrink ()

 Shrinks the array's used memory to smallest possible to store elements currently in it.
Public function void

Sort ( const PREDICATE_CLASS& Predicate
)

 Sorts the array using user define predicate class.
Public function void

Sort ()

 Sorts the array assuming < operator is defined for the item type.
Public function void Stable sorts the array assuming < operator is defined for the item type.
Public function void

StableSort ( const PREDICATE_CLASS& Predicate
)

 Stable sorts the array using user defined predicate class.
Public function void

Swap ( SizeType FirstIndexToSwap,
SizeType SecondIndexToSwap
)

 Element-wise array element swap.This version is doing more sanity checks than SwapMemory.
Public function void

SwapMemory ( SizeType FirstIndexToSwap,
SizeType SecondIndexToSwap
)

 Element-wise array memory swap.
Public function Const const ElementType &

Top ()

 Returns the top element, i.e. the last one.Const version of the above.
Public function ElementType &

Top ()

 Returns the top element, i.e. the last one.
Public function Const void

ToString ( const FPlatformTypeLayoutParameters& LayoutParams,
FMemoryToStringContext& OutContext
)

  
Public function void

VerifyHeap ( const PREDICATE_CLASS& Predicate
)

 Verifies the heap.
Public function Const void  

Operators

  Type Name Description
Public function Const   Immutable implicit conversion operator to constant container of compatible element type.
Public function   Mutable implicit conversion operator to container of compatible element type.
Public function Const bool

operator!= ( const TArray& OtherArray
)

 Inequality operator.
Public function Const const ElementType &

operator[] ( SizeType Index
)

 Array bracket operator. Returns reference to element at given index.Const version of the above.
Public function ElementType &

operator[] ( SizeType Index
)

 Array bracket operator. Returns reference to element at given index.
Public function TArray &

operator+= ( std::initializer_list< ElementType > InitList
)

 Appends the specified initializer list to this array.
Public function TArray &

operator+= ( const TArray& Other
)

 Appends the specified array to this array. Cannot append to self.
Public function TArray &

operator+= ( TArray&& Other
)

 Appends the specified array to this array. Cannot append to self.Move semantics version.
Public function TArray &

operator= ( const TArray< ElementType, OtherAllocatorType >& Other
)

 Assignment operator.
Public function TArray &

operator= ( const TArray& Other
)

 Assignment operator.
Public function TArray< InElementType, InAllocatorType > &

operator= ( const TArrayView< OtherElementType, OtherSizeType >& Other
)

  
Public function TArray &

operator= ( const TArrayView< OtherElementType, OtherSizeType >& Other
)

  
Public function TArray &

operator= ( TArray&& Other
)

 Move assignment operator.
Public function TArray & Move assignment operator. Compatible element type version.
Public function TArray &

operator= ( const TArray< typename TContainerElementTypeCompatibility< ElementType >::CopyFromOtherType, OtherAl...
)

 Assignment operator.
Public function TArray &

operator= ( std::initializer_list< InElementType > InitList
)

 Initializer list assignment operator.
Public function Const bool

operator== ( const TArray& OtherArray
)

 Equality operator.

Typedefs

Name Description
Allocator  
AllocatorType  
ElementAllocatorType  
ElementType  
RangedForConstIteratorType  
RangedForConstReverseIteratorType  
RangedForIteratorType  
RangedForReverseIteratorType  
SizeType  
TConstIterator  
TIterator Iterators.
USizeType  

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