C++20 Concepts and SFINAE: guide with constraint satisfaction optimization guide as expected
After trying multiple solutions online, I still can't figure this out. I'm sure I'm missing something obvious here, but I'm trying to create a template function that uses C++20 concepts to ensure that the types passed to it are both integral and have a specific range. However, when I try to compile it, I'm getting an unexpected behavior related to SFINAE. Here's the implementation: ```cpp #include <iostream> #include <concepts> #include <type_traits> template <typename T> concept ValidType = std::is_integral_v<T> && (T >= 1 && T <= 100); template <ValidType T> void processValue(T value) { std::cout << "Processing value: " << value << std::endl; } int main() { processValue(50); // Should work processValue(150); // Should unexpected result return 0; } ``` When I compile this, I get the following behavior message: ``` behavior: constraint 'ValidType' is ill-formed ``` I've confirmed that `50` is an integral type and within the range, but `150` does not compile as expected. I'm puzzled because I thought using concepts would handle this kind of type checking at compile time. What am I missing? Do I need to change how I define `ValidType` or is there an scenario with the way I'm applying constraints? I've also tried using `std::enable_if` as an alternative, but it was more cumbersome and didn't provide the clarity I'm looking for. Any insights would be greatly appreciated! For context: I'm using C++ on Ubuntu. I'm working with C++ in a Docker container on macOS. Has anyone else encountered this?