👀 Views: 80 💬 Answers: 1 📅 Created: 2025-06-10

cpp string string_view

I've tried everything I can think of but I'm performance testing and I've been researching this but Could someone explain I'm sure I'm missing something obvious here, but I'm working with an scenario with a custom string class that uses `std::string_view` for performance..... The conversion operator to `std::string_view` seems to cause undefined behavior when the original string is modified after the conversion. Here's a simplified version of my class: ```cpp #include <string> #include <string_view> class MyString { public: MyString(const std::string& str) : data(str) {} operator std::string_view() const { return std::string_view(data); } private: std::string data; }; ``` When I do this: ```cpp int main() { MyString myStr("Hello, World!"); std::string_view view = myStr; myStr = MyString("New String"); // Change the original string std::cout << view << std::endl; // Undefined behavior? } ``` I'm using GCC 11.2.0 and it compiles fine, but when I run it, I get a segmentation fault. It seems that the `std::string_view` is pointing to the old `std::string` data even after it has been replaced. I also tried using `const std::string&` in the conversion operator, but the behavior remains the same. Is there a best practice or a pattern I should follow to avoid this scenario? Any insights would be greatly appreciated! For context: I'm using Cpp on Ubuntu. Am I missing something obvious? I'm developing on macOS with Cpp. What's the correct way to implement this? I'm coming from a different tech stack and learning Cpp. Thanks for any help you can provide! This is happening in both development and production on Debian. What would be the recommended way to handle this? I'm working on a REST API that needs to handle this. Thanks for your help in advance!