advanced patterns with std::optional in C++20: Why is my value not being reset?
I've been struggling with this for a few days now and could really use some help. I've looked through the documentation and I'm still confused about I'm working with a puzzling scenario with `std::optional` in C++20. I have a function that is supposed to reset an `std::optional<int>` to an empty state after using it, but it seems to maintain its value unexpectedly. Here’s a simplified version of my code: ```cpp #include <iostream> #include <optional> void process(std::optional<int>& value) { if (value.has_value()) { std::cout << "Processing value: " << *value << '\n'; // Instead of resetting, I am confusingly assigning a new value but forgetting to reset it prior. value = 20; } } int main() { std::optional<int> myValue = 10; process(myValue); // Expected to see no value here after processing, but it still holds the value 20. if (!myValue) { std::cout << "myValue is empty!\n"; } else { std::cout << "myValue holds: " << *myValue << '\n'; } return 0; } ``` The output I get is: ``` Processing value: 10 myValue holds: 20 ``` I thought calling `value = {};` would reset it, but I overlooked that I'm reassigning it instead. What’s the best way to ensure `std::optional` returns to an uninitialized state after processing? I want to maintain the logic of processing but ensure that the optional is cleared afterward. Any insights or best practices regarding the usage of `std::optional` in this context would be greatly appreciated. Any help would be greatly appreciated! This is part of a larger web app I'm building. How would you solve this?