InvisibleCopies.cpp

struct FWidget 
{
    FWidget() : Name() {}
    FWidget(FString Name) : Name(Name) {}
    FWidget(const FWidget& Other) : Name(Other.Name) {}
        
    void ProcessIntensity(float Intensity) { /** **/ }
    
    FString Name;
}

//we want pass by reference of an existing list not a new copy of the list being passed in so we take an address location for WidgetsToProcess
//the list now contains pointers instead
void ProcessWidgets(const TArray<FWidget*>& WidgetsToProcess, float Intensity)
{
    //change the auto to FWidget*, we want to avoid a copy being generated in the for loop as a copy can happen during this iterated process
    for(FWidget* Widget : WidgetsToProcess)
    {
        //widget is now a pointer to . becomes ->
        Widget->ProcessIntensity(Intensity);
    }
}

//to avoid a copy, we return an address of the newly created widgets array
//the array also needs to be an array of pointers so we're iterating through, we prevent copies.
TArray<FWidget*>& CollectWidgets()
{
    TArray<FWidget*> Widgets;
    // collect
    return Widgets;
}

// returns default Widget if can't be found
//we want pass by reference of an existing list not a new copy of the list being passed in so we take an address location for WidgetsToProcess
//the list now contains pointers instead
FWidget* FindWidget(const TArray<FWidget*>& WidgetsToSearch, FString Name)
{
    //change the auto to FWidget*, we want to avoid a copy being generated in the for loop as a copy can happen during this iterated process
    for(const FWidget* Widget : WidgetsToSearch)
    {
        //widget is now a pointer to . becomes ->
        if (Widget->Name == Name)
        {
            return Widget;
        }
    }
    
    //we're returning a pointer and want to keep the reference to the newly created object on the heap (FWidget) so we return new 
    return new FWidget();
}

void Main()
{
    //widgets should contain a list of pointers, pointers we can rely on later on.
    const TArray<FWidget*> Widgets = CollectWidgets();
    
    ProcessWidgets(Widgets, 99.9f);
    
    //return a pointer to found widget
    const FWidget* Found = FindWidget(Widgets, TEXT("Find me"));
}