use crate::connection::Connection; pub trait Domain: 'static {    const NAME: &str;    const MIGRATIONS: &[&str];     fn should_allow_migration_change(_index: usize, _old: &str, _new: &str) -> bool {        false    }} pub trait Migrator: 'static {    fn migrate(connection: &Connection) -> anyhow::Result<()>;} impl Migrator for () {    fn migrate(_connection: &Connection) -> anyhow::Result<()> {        Ok(()) // Do nothing    }} impl<D: Domain> Migrator for D {    fn migrate(connection: &Connection) -> anyhow::Result<()> {        connection.migrate(            Self::NAME,            Self::MIGRATIONS,            &mut Self::should_allow_migration_change,        )    }} impl<D1: Domain, D2: Domain> Migrator for (D1, D2) {    fn migrate(connection: &Connection) -> anyhow::Result<()> {        D1::migrate(connection)?;        D2::migrate(connection)    }} impl<D1: Domain, D2: Domain, D3: Domain> Migrator for (D1, D2, D3) {    fn migrate(connection: &Connection) -> anyhow::Result<()> {        D1::migrate(connection)?;        D2::migrate(connection)?;        D3::migrate(connection)    }} impl<D1: Domain, D2: Domain, D3: Domain, D4: Domain> Migrator for (D1, D2, D3, D4) {    fn migrate(connection: &Connection) -> anyhow::Result<()> {        D1::migrate(connection)?;        D2::migrate(connection)?;        D3::migrate(connection)?;        D4::migrate(connection)    }} impl<D1: Domain, D2: Domain, D3: Domain, D4: Domain, D5: Domain> Migrator for (D1, D2, D3, D4, D5) {    fn migrate(connection: &Connection) -> anyhow::Result<()> {        D1::migrate(connection)?;        D2::migrate(connection)?;        D3::migrate(connection)?;        D4::migrate(connection)?;        D5::migrate(connection)    }}