Well, it's pretty trivial, but there are a few subtleties. Keep in mind that unsafe has another meaning when attached to a function type or trait, which intera

Well, it's pretty trivial, but there are a few subtleties. Keep in mind that unsafe has another meaning when attached to a function type or trait, which interacts with the type system. That can have surprising but necessary consequences (such as not being able to pass an unsafe function as an argument where a closure with the same signature is expected). But yeah, it's not really a first class type and it has deliberately simple semantics, so if you just want to replicate the exact functionality of unsafe in Rust you could probably do it as a lint (though for stylistic and ideological reasons I don't think Rust would ever consider doing so).