interview_rust.rs

interview_rust.rs

struct VlanInfo {
    base_iface: String,
    vlan_id: u16,
}

struct Iface {
    name: String,
    vlan_info: Option<VlanInfo>,
}

fn change_base_iface(iface: &mut Iface) {
    if let Some(mut vlan_info) = &iface.vlan_info {
        vlan_info.base_iface = "eth2".into();
    }
}

fn main() {
    let mut iface = Iface {
        name: "foo1".into(),
        vlan_info: Some(VlanInfo {
            base_iface: "eth1".into(),
            vlan_id: 1u16,
        }),
    };
    change_base_iface(&mut iface);
    if let Some(vlan_info) = iface.vlan_info {
        println!("{}", vlan_info.base_iface);
    }
}

   Compiling hello v0.1.0 (/home/fge/Source/rust_play)
error[E0507]: cannot move out of a shared reference
  --> main.rs:12:34
   |
12 |     if let Some(mut vlan_info) = &iface.vlan_info {
   |                 -------------    ^^^^^^^^^^^^^^^^
   |                 |
   |                 data moved here
   |                 move occurs because `vlan_info` has type `VlanInfo`, which does not implement the `Copy` trait

error: aborting due to previous error

For more information about this error, try `rustc --explain E0507`.
error: could not compile `hello`

To learn more, run the command again with --verbose.