Errors

Every fallible call answers Result<T, Error>, where the error carries the Status the C ABI reported and the static message beside it, so nothing allocates on the failure path. A failure the binding catches before the call crosses the boundary reports the status the engine would have used. Status carries the C enumerators’ values and leaves success to Result, so an Error never carries Status::Deferred, which only Deferred::status reports, and a status a newer library added reads as Status::Internal. Status, Mood, Durability, Watch, DropMode, Isolation, Transport, Engine, Modality, Role and Modification print through Display and parse through FromStr the spellings the C tables own, such as "not-found" or "strict-serializable", so nothing is compared as a string. ustore::version() names the library the program runs against, such as "1.0.0".

match database.head().collection_find("nowhere", &mut arena) {
    Err(failure) if failure.status == ustore::Status::NotFound => println!("{}: {failure}", failure.status),
    other => { other?; }
}