type t =
  | Relation of string * Term.t list
  | Equal of Term.t * Term.t
  | Bottom
  | Neg of t
  | Conj of t * t
  | Disj of t * t
  | Impl of t * t
  | Iff of t * t
  | Forall of t
  | Exists of t

val match_term : Term.t -> t -> t -> Term.match_result
val occurs : Term.t -> t -> bool