(motive : Lean.Exception → Sort u_1) →
  (ex : Lean.Exception) →
    ((id : Lean.InternalExceptionId) → (extra : optParam Lean.KVMap { }) → motive (Lean.Exception.internal id extra)) →
      ((ref : Lean.Syntax) → (msg : Lean.MessageData) → motive (Lean.Exception.error ref msg)) → motive ex