TRetainedRef

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Syntax

template<typename T>  
struct TRetainedRef  
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template<typename T> struct TRetainedRef

Remarks

TRetainedRef

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 InThing) : Ref(InThing) { }

... }

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

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

Specializations

TRetainedRef< const T >

Constructors

Functions

Operators