Implementing interface

fn iface_impl() -> IfaceImpl {
    let schema = schema();
    let iface = iface();

    IfaceImpl {
        schema_id: schema.schema_id(),
        iface_id: iface.iface_id(),
        global_state: tiny_bset! {
            NamedType::with(GS_NOMINAL, tn!("Nominal")),
            NamedType::with(GS_CONTRACT, tn!("ContractText")),
        },
        assignments: tiny_bset! {
            NamedType::with(OS_ASSETS, tn!("Assets")),
        },
        valencies: none!(),
        transitions: tiny_bset! {
            NamedType::with(TS_TRANSFER, tn!("Transfer")),
        },
        extensions: none!(),
    }
}