The type of return is !, not (). Meaning there are zero instances of this type (whereas there is one instance of ()). ! can coerce to any type. Also, the type

The type of return is !, not (). Meaning there are zero instances of this type (whereas there is one instance of ()). ! can coerce to any type. Also, the type of return is a separate matter from the type of the thing being returned. You obviously can't return Result from a function returning i32. The point of type coercion is that you can yield `return Err(...)` in one branch of a match and have it type check with the other branch(es).