implementing std::vector resize and iterator invalidation in C++20 after using std::move
I need help solving This might be a silly question, but I'm working with an scenario when I resize a `std::vector` and then try to access its elements using iterators after performing a `std::move` operation in C++20..... The intention was to move a collection of objects into my vector and then resize it to accommodate additional elements. However, I'm working with iterator invalidation errors that I need to seem to resolve. Here's a simplified version of my code: ```cpp #include <iostream> #include <vector> #include <string> class Item { public: Item(std::string name) : name_(std::move(name)) {} void display() const { std::cout << name_ << std::endl; } private: std::string name_; }; int main() { std::vector<Item> items; items.emplace_back("Item1"); items.emplace_back("Item2"); // Move the vector to another variable std::vector<Item> newItems = std::move(items); // Resize the new vector newItems.resize(5); // This line throws an behavior due to invalidated iterators for (auto it = newItems.begin(); it != newItems.end(); ++it) { it->display(); } return 0; } ``` The behavior I receive is related to accessing elements of `newItems` after the resize call. I thought that after moving the contents, the `resize` method would just adjust the size without invalidating existing elements. However, it seems that the behavior has changed in C++20. I've checked the documentation, and it states that resizing can invalidate iterators and references. I've tried using `std::vector::reserve` instead of `resize` before adding new elements, but that didn't help with the iterator access after moving the vector. Can anyone clarify why the iterators are invalidated in this case and suggest a way to avoid this scenario? Am I handling the `std::move` incorrectly, or is there a better practice for managing vector elements in this situation? This is happening in both development and production on Debian. What are your experiences with this? What am I doing wrong? I'm on Windows 10 using the latest version of C++. Hoping someone can shed some light on this.