Module error 

Typed errors for the core layer. No code path panics (Constitution Principle I).

Structs

BusinessReject

A business-level rejection returned from an application callback — the engine emits a BusinessMessageReject (35=j). reason is the numeric BusinessRejectReason (tag 380). FR-016.

DoNotSend

Returned from an outbound callback to suppress a message: the engine does not send it and does not store it as sent (it consumes no outbound sequence number). FR-016.

Reject

A session-level rejection returned from an admin/logon callback — the engine emits a Reject (35=3). Typed, not stringly (Constitution Principle I; FR-016). reason is the numeric SessionRejectReason (tag 373).

Enums

DecodeError

Error decoding raw bytes into a Message.

FieldError

Error converting a field’s raw value to a typed Rust value.