PromiseException

Errors that can be thrown by the Promise machinery itself (separate from user errors surfaced via reject(_:)).

Types

Thrown by await() when the Promise was cancelled via .cancel() before resolving.

Returned by await() when the promise resolves with a null/missing result.

Generic resolution failure used as a fallback when neither a value nor an error is present.

await() did not receive a result before its timeout (when a timeout is configured).

A validation step inside a chained operation failed.