Enum Error 

pub enum Error<E> {
    Original(E),
    Keel(OutcomeError),
}

The error a #[keel::wrap]-wrapped function or crate::KeelMiddleware surfaces.

Original is your own code’s error, unchanged, from the attempt the engine actually ran last (DX invariant 5’s “re-raise the original exception unchanged”, ported to a typed enum since Rust has no untyped exceptions to re-raise). Keel is a judgment the engine made without ever calling your code: a circuit breaker fast-fail (KEEL-E012), a rate budget rejection (KEEL-E013), or a non-idempotent call correctly left un-retried (KEEL-E014) — see contracts/error-codes.json for the full taxonomy.

Variants

Original(E)

Your code/library’s own error from the last attempt.

Keel(OutcomeError)

A judgment the engine made without calling your code.

Implementations

impl<E> Error<E>

pub const fn code(&self) -> Option<ErrorCode>

The KEEL-E0NN code the engine assigned, if this is a Error::Keel judgment rather than your own code’s Error::Original error.

pub fn into_original(self) -> Option<E>

Recover your code/library’s original error, if this wraps one — an engine judgment made without ever calling your code has none to give back.

Trait Implementations

impl<E: Debug> Debug for Error<E>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<E: Display> Display for Error<E>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<E: Debug + Display> Error for Error<E>

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.