Very nice text. As i am very sceptical to Rust i apreciate the comarison to a language i know better. I was not aware that there is no formal spec for rust. Isn't that a problem if rustc makes changes?
1. There is a spec now, Ferrocene donated theirs, and the project is currently integrating it
2. The team takes backwards compatibility seriously, and uses tests to help ensure the lack of breakage. This includes tests like “compile the code being used by Linux” and “compile most open source Rust projects” to show there’s no regressions.
I guess this is terminology confusion on behalf of Surac, who probably just wants a specification that is independent of the rustc implementation.
For implementers of third-party compilers, researchers of the Rust programming language, and programmers who write unsafe code, this is indeed a problem. It's bad.
For the designers of Rust, "no formal specification" allows them to make changes as long as it is not breaking. It's good.