Macro smithay::define_roles

macro_rules! define_roles {
    ($enum_name: ident) => { ... };
    ($enum_name:ident => $([ $role_name: ident, $role_data: ty])*) => { ... };
    (__impl $enum_name:ident => $([ $role_name: ident, $role_data: ty])*) => { ... };
}