Pointers to member functions are very strange animals Answer to exercise: Pointer to member function cast Member Function Pointers and the Fastest Possible C++ Delegates 更新(4/12/2012):研究了下FastDelegates的代码,针对VC,好像我的理解还是有点偏差。
The low bit of a function pointer to a non-static member function is never set. On most platforms, this is either always true or can be made true at little cost. For example, on platforms where a function pointer is just the address of the first instruction in the function, the impleme...
int main() { // Declare a member function pointer for SomeClass typedef void (SomeClass::*SomeClassMFP)(int, char *); SomeClassMFP my_memfunc_ptr; my_memfunc_ptr = &DerivedClass::some_member_func; // --- line (*) DerivedClass *dc; dc->*my_memfunc_ptr(1,""); } #include ...
Output 复制 is_member_pointer<trivial *> == false is_member_pointer<int trivial::*> == true is_member_pointer<int (functional::*)()> == true 要求 标头:<type_traits> 命名空间: std 另请参阅 <type_traits> is_member_function_pointer 类 is_member_object_pointer 类 is_pointer 类反馈...
Function Pointers We begin with a review of function pointers. In C, and consequently in C++, a function pointer called my_func_ptr that points to a function taking an int and a char * and returning a float, is declared like this: float (*my_func_ptr)(int, char *); // To make ...
To answer your question why this works: just like the array-to-pointer decay there is a function-to-pointer decay (inherited from C), but it doesn't include member-function-to-pointer decay. You have to take their address explicitly (so your question really should have been: why does it...
C++ Pointer to Member Function A challenge for every C++ programmer are pointer to member functions (ptmf).ptmfs are diffent than their C counterparts - function pointers (fp). Using function pointers in C is a common practice and gives the programmer a powerful technique for a good pice of...
The errors generated from attempting to call a non-const member function on a const object can be a little cryptic: error C2662: 'int Something::getValue(void)': cannot convert 'this' pointer from 'const Something' to 'Something &' error: passing 'const Something' as 'this' argument dis...
base1.print();// Output: Base Function Access Shadowed Function in C++ To access the shadowed function of the base class, we use the scope resolution operator::. We can also access the shadowed function by using apointerof the base class to point to an object of the derived class and ...
I have to call gsl functions (which are written in c) from a c++ class. And I need to pass a function pointer of the form double (*)(double, void*). How can i manage this? Apr 27, 2009 at 10:57pm helios(17607) Sounds like a classic callback function. You typically just write...