> When you hit one of these problems you can just look at what other implementations do in practice. Rust doesn't even have anything resembling a spec. But it

> When you hit one of these problems you can just look at what other implementations do in practice. Rust doesn't even have anything resembling a spec. But it does have a reference implementation. The first quoted sentence is what alternative implementations are already doing: looking at what `rustc` does and ask for clarification upstream when necessary. I can envision cases where `rustc`'s behavior isn't what was intended being uncovered when trying to reach parity, and changing `rustc` to conform to an explicit intent, however unlikely this might be in practice.