diff --git a/compiler/heptagon/transformations/present_mapfold.ml b/compiler/heptagon/transformations/present_mapfold.ml
new file mode 100644
index 0000000..cb9935b
--- /dev/null
+++ b/compiler/heptagon/transformations/present_mapfold.ml
@@ -0,0 +1,34 @@
+(**************************************************************************)
+(*                                                                        *)
+(*  Heptagon                                                              *)
+(*                                                                        *)
+(*  Author : Marc Pouzet                                                  *)
+(*  Organization : Demons, LRI, University of Paris-Sud, Orsay            *)
+(*                                                                        *)
+(**************************************************************************)
+(* removing present statements *)
+open Heptagon
+open Hept_mapfold
+
+let translate_present_handlers handlers cont =
+  let translate_present_handler { p_cond = e; p_block = b } cont =
+    let statefull = b.b_statefull or cont.b_statefull in
+      mk_block ~statefull:statefull b.b_defnames
+        [mk_switch_equation
+           ~statefull:statefull e
+           [{ w_name = Initial.ptrue; w_block = b };
+            { w_name = Initial.pfalse; w_block = cont }]] in
+  let b = List.fold_right translate_present_handler handlers cont in
+    (List.hd (b.b_equs)).eq_desc
+
+let eqdesc funs acc eqd =
+  let eqd, _ = Hept_mapfold.eqdesc funs acc eqd in
+    match eqd with
+      | Epresent(ph, b) -> translate_present_handlers ph b, acc
+      | _ -> eqd, acc
+
+let program p =
+  let funs = { Hept_mapfold.defaults with eqdesc = eqdesc } in
+  let p, _ = Hept_mapfold.program_it funs false p in
+    p
+