comment about possible alternate format

recanalyser/recAnalyser.ml

@@ -34,6 +34,12 @@ type rec_info =
 *)
 external analyse_core : rec_descr -> Obj.t -> string = "coq_rec_analyse"
 
+(* XXX it seems in practice sequences of fresh nodes are common, so we get a bunch of 0s
+   maybe it would be better to change the format to a sequence of
+   "the next $n are fresh" and "non fresh id $n"
+   instead of the current "1 fresh" and "non fresh id $n".
+*)
+
 type analysis = {
   data : string;
   offset : int;