[sledge] Add Trm.Set.pp

Reviewed By: jvillard

Differential Revision: D25756563

fbshipit-source-id: acf4f46fc

sledge/src/fol/trm.ml

@@ -385,11 +385,14 @@ end
 
 module T = struct
   type t = Trm.t [@@deriving compare, sexp]
+
+  let pp = Trm.pp
 end
 
 module Set = struct
   include Set.Make (T)
   include Provide_of_sexp (T)
+  include Provide_pp (T)
 end
 
 module Map = struct

sledge/src/fol/trm.mli

@@ -41,6 +41,7 @@ module Set : sig
   include Set.S with type elt := t
 
   val t_of_sexp : Sexp.t -> t
+  val pp : t pp
 end
 
 module Map : sig