addressof

How do I decide whether I need addressof(x) instead of &x when taking the address of an object? Seems like the question was confusing, so a clarification is in order: addressof obviously bypasses the overloaded address-of operator. I'm already aware of that. What I want to know is: How do I know if that's what I really want to do? (Especially when inside a template, etc.) Is there some kind of "rule" that helps me figure out when I need addressof instead of & ? After all, they both return the "address of" the object, so when do I use which? You use std::addressof when you have to. Sadly, "when

I know about all about pointers and the ampersand means "address of" but what's it mean in this situation? Also, when overloading operators, why is it common declare the parameters with const? Kyle Walsh In that case you are returning a reference to an ostream object. Strictly thinking of ampersand as "address of" will not always work for you. Here 's some info from C++ FAQ Lite on references. As far as const goes, const correctness is very important in C++ type safety and something you'll want to do as much as you can. Another page from the FAQ helps in that regard. const helps you from side

When option strict is OFF, works fine. ON, I get overload resolution failure: Dim _thread1 As Thread Private Sub test2(boolTest As Boolean) ' Do something End Sub ' Private Sub test() _thread1 = New Thread(AddressOf test2) _thread1.Start(True) End Sub Overload resolution failed because no accessible 'New' can be called with these arguments: 'Public Sub New(start As System.Threading.ParameterizedThreadStart)': Option Strict On does not allow narrowing in implicit type conversions between method 'Private Sub test2(boolTest As Boolean)' and delegate 'Delegate Sub ParameterizedThreadingStart(obj

I got an official answer to this question that decltype should not trigger function compilation. In fact decltype on a function that is declared but not defined is legal. Next question, should taking the address of a function trigger the compilation of a function? Take this example : template <typename T> void foo(T&& x) { x.func(); } int main() { auto bar = &foo<int>; } All the compilers I've tested fail with an error like: Request for member func in x , which is of non-class type int But if I just define foo and don't declare it, the code compiles fine. Can someone provide me with an

I am a teaching assistant of a introductory programming course, and some students made this type of error: char name[20]; scanf("%s",&name); which is not surprising as they are learning... What is surprising is that, besides gcc warning, the code works (at least this part). I have been trying to understand and I wrote the following code: void foo(int *v1, int *v2) { if (v1 == v2) printf("Both pointers are the same\n"); else printf("They are not the same\n"); } int main() { int test[50]; foo(&test, test); if (&test == test) printf("Both pointers are the same\n"); else printf("They are not the

As the title says, I always wonder why scanf must take the address of operator (&). Because C only has "pass-by-value" parameters, so to pass a 'variable' to put a value into, you have to pass its address (or a pointer to the variable). Andrew Medico scanf does not take "the address of operator (&)". It takes a pointer . Most often the pointer to the output variable is gotten by using the address-of operator in the scanf call, e.g. int i; scanf("%i", &i); printf("number is: %d\n", i); But that is not the only way to do it. The following is just as valid: int* iPtr = malloc(sizeof(int)); scanf(