The C++23 standard will feature a new utility type called std::expected. This type either contains an expected value, or an unexpected one, typically providing information about the reason something failed (and the expected value could not be returned). This feature is, at this time, supported in GCC 12 and MSVC 19.33 (Visual Studio 2022 17.3). In this article, we’ll see what std::expected is and how it can be used.
