TRetainedRef< T > Struct Template Reference

#include <RetainedRef.h>

Public Member Functions
	TRetainedRef (T &InRef)
	TRetainedRef (const T &InRef)=delete
	TRetainedRef (T &&InRef)=delete
	TRetainedRef (const T &&InRef)=delete
	operator T& () const
T &	Get () const

Detailed Description

template<typename T>
struct TRetainedRef< T >

TRetainedRef<T>

A helper class which replaces T& as a function parameter when the reference is intended to be retained by the function (e.g. as a class member). The benefit of this class is that it is a compile error to pass an rvalue which might otherwise bind to a const reference, which is dangerous when the reference is retained.

Example:

struct FRaiiType { explicit FRaiiType(const FThing& InThing) : Ref(InThing) { }

void DoSomething() { Ref.Something(); }

FThing& Ref; };

void Test() { FThing Thing(...); FRaiiType Raii1(Thing); // Compiles Raii.DoSomething(); // Fine

FRaiiType Raii2(FThing(...)); // Compiles Raii.DoSomething(); // Illegal - reference has expired! }

But if the constructor is changed to use TRetainedRef then it fixes that problem:

struct FRaiiType { explicit FRaiiType(TRetainedRef<const FThing> InThing) : Ref(InThing) { }

... }

FThing Thing(...); FRaiiType Raii1(Thing); // Compiles Raii.DoSomething(); // Fine

FRaiiType Raii2(FThing(...)); // Compile error! Raii.DoSomething();

Constructor & Destructor Documentation

TRetainedRef() [1/4]

template<typename T >

TRetainedRef< T >::TRetainedRef ( T &  InRef )

inline

TRetainedRef() [2/4]

template<typename T >

TRetainedRef< T >::TRetainedRef ( const T &  InRef )

delete

TRetainedRef() [3/4]

template<typename T >

TRetainedRef< T >::TRetainedRef ( T &&  InRef )

delete

TRetainedRef() [4/4]

template<typename T >

TRetainedRef< T >::TRetainedRef ( const T &&  InRef )

delete

Member Function Documentation

Get()

template<typename T >

T & TRetainedRef< T >::Get ( ) const

inline

operator T&()

template<typename T >

TRetainedRef< T >::operator T& ( ) const

inline

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The documentation for this struct was generated from the following file:

• Engine/Source/Runtime/Core/Public/Templates/RetainedRef.h