check robot field

lib/ast.ml

@@ -273,6 +273,10 @@ let info_space (i : information):bool =
   | Space _ -> true
   | _        -> false
 
+let info_robot (i : information):bool = 
+  match i with
+  | Robot _ -> true
+  | _        -> false
 
 (*GRAPH*)
 module Node = struct                                                                
@@ -450,7 +454,10 @@ let check_light d : bool =
 													      else (
                                   if not(unique info_space d') 
                                     then raise(Failure "Error: Problem of defining space")
-													        else true
+                                else (
+                                  if not(unique info_robot d') 
+                                    then raise(Failure "Error: Problem of defining sensors")
+													        else true)
 														  ) 
       in if  check_light d && check_activelyup d && check_sensors_desc d && aux d then true else false                   
 ;;