3.1. Guard Evaluation🔗

MailboxActors.GuardEvalStep determines whether a single guarded action fires or fails. It has two constructors:

• B-GuardedActionEval (MailboxActors.GuardEvalStep.guardMatch) — the guard returns some w, and the action produces an effect using the witness and the proof that the guard holds.

• B-NoMatchingGuard (MailboxActors.GuardEvalStep.guardFail) — the guard returns none, producing Effect.noop.