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> Unreal Engine API Reference > Runtime > Core > Containers > TUnion

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TUnion

Represents a type which is the union of several other types; i.e. it can have a value whose type is of any the union's subtypes.

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References

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

Syntax

template<typename TypeA, typename TypeB, typename TypeC, typename TypeD, typename TypeE, typename TypeF>
class TUnion

Remarks

Represents a type which is the union of several other types; i.e. it can have a value whose type is of any the union's subtypes. This differs from C union types by being type-safe, and supporting non-trivial data types as subtypes. Since a value for the union must be of a single subtype, the union stores potential values of different subtypes in overlapped memory, and keeps track of which one is currently valid.

Variables

		Name	Description
	TTypeCompatible...	A
	TTypeCompatible...	B
	TTypeCompatible...	C
	TTypeCompatible...	D
	TTypeCompatible...	E
	TTypeCompatible...	F

Constructors

	Name	Description
	TUnion()	Default constructor.
	TUnion ( const TUnion& Other )	Copy constructor.
	TUnion ( typename TCallTraits< TypeA >::Para..., TDisambiguater< 0 > Disambiguater )	Initialization constructor.
	TUnion ( typename TCallTraits< TypeB >::Para..., TDisambiguater< 1 > Disambiguater )	Initialization constructor.
	TUnion ( typename TCallTraits< TypeC >::Para..., TDisambiguater< 2 > Disambiguater )	Initialization constructor.
	TUnion ( typename TCallTraits< TypeD >::Para..., TDisambiguater< 3 > Disambiguater )	Initialization constructor.
	TUnion ( typename TCallTraits< TypeE >::Para..., TDisambiguater< 4 > Disambiguater )	Initialization constructor.
	TUnion ( typename TCallTraits< TypeF >::Para..., TDisambiguater< 5 > Disambiguater )	Initialization constructor.

Destructors

	Name	Description
	~TUnion()	Destructor.

Functions

	Name	Description
uint8	GetCurrentSubtypeIndex()
Subtype &	GetSubtype()
const Subtyp...	GetSubtype()
bool	HasSubtype()
void	Reset()	Sets the union's value to NULL.
void	ResetSubtype()	If the union's current value is of the given subtype, sets the union's value to a NULL value.
Subtype *...	SetSubtype ( typename TCallTraits< Subtype >::Pa... )	Replaces the value of the union with a value of the given subtype.

Operators

		Name	Description
	TUnion &	operator= ( const TUnion& Other )
	bool	operator== ( const TUnion& Other )	Equality comparison.

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