diff --git a/sw/ground_segment/cockpit/papgets.ml b/sw/ground_segment/cockpit/papgets.ml
index b887083eeff..18da2c3ff6c 100644
--- a/sw/ground_segment/cockpit/papgets.ml
+++ b/sw/ground_segment/cockpit/papgets.ml
@@ -43,11 +43,9 @@ let papget_listener =
     try
       let field = Papget_common.get_property "field" papget in
       let sender = try Some (Papget_common.get_property "ac_id" papget) with _ -> None in
-      match Str.split sep field, sender with
-          [msg_name; field_name], Some sender ->
-            (new Papget.message_field ~sender msg_name field_name)
-        | [msg_name; field_name], None ->
-            (new Papget.message_field msg_name field_name)
+      match Str.split sep field with
+          [msg_name; field_name] ->
+            (new Papget.message_field ?sender msg_name field_name)
         | _ -> failwith (sprintf "Unexpected field spec: %s" field)
     with
         _ -> failwith (sprintf "field attr expected in '%s" (Xml.to_string papget))
@@ -76,9 +74,7 @@ let expression_listener = fun papget ->
   let expr = Papget_common.get_property "expr" papget in
   let expr = Expr_lexer.parse expr in
   let sender = try Some (Papget_common.get_property "ac_id" papget) with _ -> None in
-  match sender with
-    Some sender -> new Papget.expression ~extra_functions ~sender expr
-  | None -> new Papget.expression ~extra_functions expr
+  new Papget.expression ~extra_functions ?sender expr
 
 
 
diff --git a/sw/lib/ocaml/papget.ml b/sw/lib/ocaml/papget.ml
index 2e79863ddbd..93b45bcac98 100644
--- a/sw/lib/ocaml/papget.ml
+++ b/sw/lib/ocaml/papget.ml
@@ -94,10 +94,7 @@ let hash_vars = fun ?sender expr ->
     | E.Deref (_e, _f) as deref -> fprintf stderr "Warning: Deref operator is not allowed in Papgets expressions (%s)" (E.sprint deref)
     | E.Field (i, f) ->
       if not (Hashtbl.mem htable (i,f)) then
-        let msg_obj = match sender with
-            Some sender -> new message_field ~sender i f
-          | None -> new message_field i f
-        in
+        let msg_obj = new message_field ?sender i f in
         Hashtbl.add htable (i, f) msg_obj in
   loop expr;
   htable
@@ -136,10 +133,7 @@ let eval_expr = fun (extra_functions:(string * (string list -> string)) list) h
 
 
 class expression = fun ?(extra_functions=[]) ?sender expr ->
-  let h = match sender with
-      Some sender -> hash_vars ~sender expr
-    | None -> hash_vars expr
-  in
+  let h = hash_vars ?sender expr in
 object
   val mutable callbacks = []
   val mutable last_value = "0."