struct r { i: @mut int, } impl r : Drop { fn finalize(&self) { *(self.i) += 1; } } fn r(i: @mut int) -> r { r { i: i } } fn main() { let i = @mut 0; // Even though these look like copies, they are guaranteed not to be { let a = r(i); let b = (move a, 10); let (c, _d) = move b; log(debug, c); } assert *i == 1; }