advanced patterns with std::optional in C++20 when Using Member Function Pointers
I'm trying to configure I've been researching this but I've been struggling with this for a few days now and could really use some help..... I'm working with an unexpected scenario with `std::optional` in C++20 when trying to store member function pointers. The goal is to have a function that takes a member function pointer of a class and returns an optional value based on whether that member function is callable. However, I run into issues when trying to invoke the member function pointer if it is not initialized. Here's a simplified version of what I've tried: ```cpp #include <iostream> #include <optional> class MyClass { public: void myMethod() { std::cout << "Hello, World!" << std::endl; } }; std::optional<void (MyClass::*)()> getMethod(bool condition) { if (condition) { return &MyClass::myMethod; } return std::nullopt; } int main() { MyClass obj; auto methodPtr = getMethod(false); if (methodPtr) { (obj.*methodPtr)(); // This fails when methodPtr is empty } else { std::cerr << "No method available" << std::endl; } return 0; } ``` When I run this code, it compiles without errors, but during execution, if `getMethod` returns an empty `std::optional`, I end up with a runtime behavior. I expected the `else` branch to handle the case where no method is available, but the invocation of the member function pointer shouldn't happen if the optional is empty. I thought `std::optional` would prevent this by not allowing dereferencing of an empty value. I've also tried checking the optional before dereferencing, but I must have missed something. Is there a specific way to safely handle member function pointers stored in `std::optional`? Any insights or best practices would be appreciated! What's the best practice here? Any help would be greatly appreciated! Any ideas how to fix this?