Using exceptions in C++ desktop and server applications overall made sense to me. As I expanded my usage of C++ into other domains, specifically embedded domains, I began to experience more compelling reasons not to use exceptions first-hand…
From lobste.rs
The discussion is on to use monads in C++, and not on why is C++ different than Rust.
I repeat: you do not need sum types to implement a Result monad in C++.
The discussion was about sum types. The top-level comment, the one to which you originally responded, says: