Record rule := Rule {
  (** The rule conclusion. *)
  rConclusion   : ruleConclusion;
  (** The expression that matches a subject. *)
  rMatchSubject : exprMatchSubject;
  (** The expression that matches an object. *)
  rMatchObject  : exprMatchObject;
  (** The expression that matches a subject. *)
  rMatchAction  : exprMatchAction
}.
