Unexpected behavior with std::function when capturing lambdas in C++17
I'm confused about I'm experiencing unexpected behavior when using `std::function` to store lambdas that capture local variables in my C++17 project. I have a simple example where I create a function that takes a lambda as an argument, which captures a variable by value. However, when I invoke the stored `std::function` later, it doesn't seem to retain the correct value of the captured variable. Here's a simplified version of my code: ```cpp #include <iostream> #include <functional> #include <vector> void registerCallback(std::function<void()> callback) { callback(); } int main() { int x = 10; std::function<void()> myFunc = [x]() { std::cout << "Value of x: " << x << std::endl; }; registerCallback(myFunc); x = 20; // Changing the value of x after the lambda capture registerCallback(myFunc); return 0; } ``` When I run this code, I expect the first call to `registerCallback` to print `Value of x: 10` and the second call to print `Value of x: 10` again since the lambda captures `x` by value. However, I keep getting `Value of x: 10` for both calls, which is what I expect, but I need to understand why the output remains the same even after modifying `x` after capturing. I thought the lambda should have its own copy of `x`. Is there something I'm missing about how lambdas capture variables in C++17? I tried using a raw function pointer instead of `std::function`, but that results in a compilation error due to the lambda's context. Any insights would be helpful! Any ideas what could be causing this? This issue appeared after updating to C++ 3.9. Is there a better approach?