Fact.ConcurrencyError exception (Fact v0.2.0)

This exception is raised when the optimistic concurrency control logic determines an event or events cannot be written to the ledger.

The following fields of this exception are public and can be accessed:

• :source - the event store (:all) or the event stream
• :expected - the expectation or position during the append operation
• :actual - the actual position during the append operation