gistfile1.rs

#[deriving(ToStr)]
struct Vec3f {
    x: f32, 
    y: f32, 
    z: f32
}

macro_rules! impl_vec_op(
    ($tr: ident, $op: ident, $vt: ident, $($members: ident)+) => (
        impl $tr<$vt, $vt> for $vt {
            fn $op(&self, other: &$vt) -> $vt {
                $vt { $( $members: self.$members.$op(&other.$members) ),+ }
            }
        }
    );
)
macro_rules! impl_vec_ops(
    ($vt: ident, $($members: ident)+) => (
        impl_vec_op!(Sub, sub, $vt, $( $members )+)
        impl_vec_op!(Add, add, $vt, $( $members )+)        
    );
)

impl_vec_ops!(Vec3f, x y z)


fn main() {
    let a = Vec3f {x: 0.0, y: 1.0, z: 0.0};
    let b = Vec3f {x: 0.0, y: 0.0, z: 1.0};
    println((a + b).to_str());
    println((a - b).to_str());
}

gistfile2.txt

main.rs:30:13: 30:18 error: binary operation + cannot be applied to type `Vec3f`
main.rs:30     println((a + b).to_str());
                        ^~~~~
error: aborting due to previous error