Rust has a bad day with side-effects.

gistfile1.rs

struct S { x: int, y: int }
fn effect(s: &str) -> S { io::println(s); S { x: 0, y: 0 } }

pub fn main() {
	let _foo = S { x: 1, .. effect("this will be printed") };
	let _ = S { x: 2, .. effect("and this won't") };
	let _ = S { x: effect("but this will").y, .. effect("(still no)") };
}