2 files changed, 12 insertions, 6 deletions

diff --git a/reg.ml b/reg.ml
index 133ef21..d065838 100644
--- a/reg.ml
+++ b/reg.ml
@@ -8,7 +8,7 @@ open Common
 let reg_idx (Reg(idx, _)) = idx
 let reg_val (Reg(_, value)) = value
 let reg_compar l r = (reg_val l) - (reg_val r)
-let reg_string (Reg (index, value)) = (string_of_int index) ^ ": " ^ (string_of_int value)
+let reg_string (Reg (index, value)) = "(" ^ (string_of_int index) ^ "," ^ (string_of_int value) ^ ")"
 
 let regs_get reglist index =
   List.find (fun (Reg(idx, _)) -> idx = index) reglist |> reg_val
@@ -16,5 +16,5 @@ let regs_get reglist index =
 let regs_set reglist index value =
   Reg(index, value) :: List.filter (fun (Reg(idx, _)) -> idx != index) reglist
 
-let regs_string reglist = List.map (reg_string) reglist |> String.concat ", "
+let regs_string reglist = List.map (reg_string) reglist |> String.concat ","
 
diff --git a/urm.ml b/urm.ml
index be9f7e4..3b7068b 100644
--- a/urm.ml
+++ b/urm.ml
@@ -23,12 +23,18 @@ let urm_apply urm =
     | _, _ -> { instptr = urm.instptr ; regs = urm.regs } |> urm_move_down
   in if instptr_end urm.instptr then urm else aux (instptr_get urm.instptr)
 
-(* Launches the URM *)
-let rec urm_run = function
+let rec urm_run_pre pre = function
   | { instptr = InstPtr(_, []) ; regs = reg_list } -> reg_list
-  | urm -> urm_apply urm |> urm_run
+  | urm -> pre urm; urm_apply urm |> urm_run_pre pre
 
-let urm_run_trace = urm_run (* TODO *)
+let urm_run = urm_run_pre (fun _ -> ())
+
+let urm_run_trace =
+  let print_func u =
+    print_endline (instptr_string u.instptr);
+    print_endline (regs_string u.regs);
+    print_newline ()
+  in urm_run_pre (print_func)
 
 (* Creates an URM from a command list and a register list *)
 let urm_mk cmd_list reg_list = { instptr = (instptr_mk cmd_list) ; regs = reg_list }