lurette 0.13 Thu, 22 Nov 2001 13:53:30 +0100 by jahier

Parent-Version:      0.12
Version-Log:

Just a few cosmetic changes.

Project-Description: Lurette

.lurette.prcs_aux

@@ -2,35 +2,38 @@
 ;; REALLY bad things.
 (Created-By-Prcs-Version 1 3 3)
 (vrai.h 1120 1006183551 31_vrai.h 1.1)
-(env.mli 3513 1006182545 15_env.mli 1.3)
+(env.mli 3457 1006433610 15_env.mli 1.4)
 (test.aut 644 1003928781 22_test.aut 1.1)
 (Mercury/graph.m 15076 1002205313 7_graph.m 1.1)
 (Mercury/lurette.m 4239 1002789994 5_lurette.m 1.5)
 (edge.h 1052 1006263320 33_edge.h 1.1)
 (ID_EN_VRAC 2184 1002196285 0_ID_EN_VRAC 1.1)
-(env.ml 24541 1006263320 16_env.ml 1.6)
+(env.ml 24680 1006433610 16_env.ml 1.7)
 (Mercury/test.aut 1231 1002546062 8_test2.aut 1.1)
 (doc/Interface_draft 5232 1003928781 19_Interface_ 1.1)
+(tram_simple.c 5627 1006433610 37_tram_simpl 1.1)
 (Mercury/Mmakefile 102 1002789994 1_Mmakefile 1.3)
 (doc/archi.fig 3693 1003928781 20_archi.fig 1.1)
 (make_lurette 1121 1006263320 27_make_luret 1.3)
-(Makefile 331 1006263320 18_Makefile 1.6)
+(Makefile 332 1006433610 18_Makefile 1.7)
 (interface/Makefile 123 1006263320 25_Makefile 1.4)
 (OcamlMakefile 15015 1004519854 17_OcamlMakef 1.2)
 (interface/TAGS 1497 1006182545 26_TAGS 1.2)
 (README 0 1002791390 10_README 1.1)
+(tram_simple.h 1746 1006433610 36_tram_simpl 1.1)
 (Mercury/env.m 9937 1003928781 4_env_automa 1.5)
 (random_bool.aut 418 1006182545 29_random_boo 1.1)
-(interface/gen_stubs.ml 31527 1006263320 24_generate_l 1.7)
+(interface/gen_stubs.ml 31628 1006433610 24_generate_l 1.8)
 (Mercury/dot_automata.m 5814 1002546062 9_dot_automa 1.1)
 (Mercury/dot.m 3636 1002298322 6_dot.m 1.2)
 (Mercury/memory.m 3884 1002196285 3_memory.m 1.1)
 (vrai.lus 65 1006182545 28_vrai.lus 1.1)
 (graph.mli 1305 1003932490 13_graph.mli 1.2)
 (graph.ml 2397 1003932490 14_graph.ml 1.2)
-(lurette.mli 45 1006263320 11_lurette.ml 1.4)
+(lurette.mli 44 1006433610 11_lurette.ml 1.5)
 (TAGS 5673 1006182545 21_TAGS 1.5)
 (vrai.c 1405 1006183551 30_vrai.c 1.1)
-(lurette.ml 5245 1006263320 12_lurette.ml 1.7)
+(util.ml 2865 1006433610 35_util.ml 1.1)
+(lurette.ml 5064 1006433610 12_lurette.ml 1.8)
 (interface/sut_idl_stub.ml 338 1006263457 34_sut_idl_st 1.1)
 (edge.c 1693 1006263320 32_edge.c 1.1)

Makefile

@@ -7,7 +7,7 @@ SOURCES = $(SUT) \
           $(ORACLE) \
           oracle_stub.c  oracle_idl_stub.idl \
           lurette_stub.ml \
-          util.ml graph.mli graph.ml env.mli env.ml lurette.mli lurette.ml
+          util.ml  graph.mli graph.ml env.mli env.ml lurette.mli lurette.ml
 RESULT  = lurette
 
 -include $(OCAMLMAKEFILE)

env.mli

@@ -39,7 +39,7 @@ open Lurette_stub
 
 type var_type = string
 type var_name = string
-type var_name_and_type = var_name * var_type
+type vnt = var_name * var_type
 type date
 type formula_eps
 type formula
@@ -72,9 +72,9 @@ type env_stateT = {
 
 
 val read_env_state : string -> 
-    var_name_and_type list (* Environment input  variable names and types *)
-  * var_name_and_type list (* Environment output variable names and types *)
-  * var_name_and_type list (* Environment local  variable names and types *)
+    vnt list (* Environment input  variable names and types *)
+  * vnt list (* Environment output variable names and types *)
+  * vnt list (* Environment local  variable names and types *)
 (*
 ** [read_env_state file] updates the global variable `env_state' 
 ** using the content of file `file'. Also returns the new lists

interface/gen_stubs.ml

@@ -602,9 +602,9 @@ let (generate_lurette_stub_file: vn_ct_mlt_fvn list * vn_ct_mlt_fvn list -> unit
        *)
       fun mlt fvn -> 
 	match mlt with
-	    "int" -> put "    print_int "; put fvn 
-	  | "bool" -> put "    print_bool "; put fvn 
-	  | "float" -> put "    print_float "; put fvn 
+	    "int" -> put "    print_int "; put fvn ; put "; print_string \" \"" 
+	  | "bool" -> put "    print_bool "; put fvn ; put "; print_string \" \"" 
+	  | "float" -> put "    print_float "; put fvn ; put "; print_string \" \"" 
 	  | _ -> put "print_string \"***\";\n" ;
     in
     let vnl_in =  List.map (fun (w,x,y,z) -> w) sut_in in
@@ -717,8 +717,8 @@ let (generate_lurette_stub_file: vn_ct_mlt_fvn list * vn_ct_mlt_fvn list -> unit
       
 							    
        (*
-       ** I define that type here because I need it here ...
-       ** XXX Could I define it in env.ml and use it here? --> check that.
+       ** I define that type here because I both need it here and in env.ml, 
+       ** and this (generated) module is already imported by env.ml ...
        *)
       put ("type atomic_expr = \n" ^
 	  "  | Int of int\n" ^
@@ -727,7 +727,7 @@ let (generate_lurette_stub_file: vn_ct_mlt_fvn list * vn_ct_mlt_fvn list -> unit
 	  "\n\n") ;
 
       (*
-       ** Defines 2 functionq to access a value from the inputs and outputs
+       ** Defines 2 functions to access a value from the inputs and outputs
        ** given a variable name. For example, if sut_try have the ml type
        ** `int -> bool -> float -> bool * int', where the corresponding variable
        ** names are respectively "a_i", "b", "f", "res_b" and "res_i", then 

interface/util.ml

+../util.ml
\ No newline at end of file

lurette.ml

@@ -18,15 +18,15 @@ open Util
 (* 
 ** [var_decl_are_inconsistent in_env out_env in_sut out_sut]
 ** checks the consistency of variable declarations made in the environment
-** and the SUT. Raises an exception if the decla are inconsistents.
+** and the SUT. Raises an exception if the declarations are inconsistents.
 *)
  
 let print_var_list vl = 
   List.iter (fun (v, t) -> print_string ("\n   " ^  v ^ " of type " ^ t ^ ",")) vl  
     
 let (var_decl_are_inconsistent : 
-       var_name_and_type list -> var_name_and_type list 
-	 -> var_name_and_type list -> var_name_and_type list 
+       vnt list -> vnt list 
+	 -> vnt list -> vnt list 
 	     -> unit) =
   fun in_env out_env in_sut out_sut ->
       if not(list_are_equals out_env in_sut) then
@@ -50,9 +50,10 @@ let (var_decl_are_inconsistent :
 
 (*------------------------------------------------------------------------*)
 
-let (read_var_names: string -> var_name_and_type list * var_name_and_type list) =
+let (read_var_names: string -> vnt list * vnt list) =
   fun file ->
-    let rec (read_var_list: in_channel -> var_name_and_type list -> var_name_and_type list) =
+    let rec (read_var_list: in_channel -> vnt list -> 
+	       vnt list) =
       fun ic acc -> 
 	let str = input_line ic in
 	  if ((str = "\\\\OUTPUT") || (str = "\\\\THE_END"))
@@ -84,20 +85,21 @@ let rec (main : int -> int -> 'a) =
       with Failure(err_msg) -> (print_string err_msg)
 and
   (read_list_of_aut: int -> 
-     var_name_and_type list * var_name_and_type list * var_name_and_type list -> 
-       var_name_and_type list * var_name_and_type list * var_name_and_type list ) =
+     vnt list * vnt list * vnt list -> 
+       vnt list * vnt list * vnt list ) =
   fun cpt (in0, out0, loc0) -> 
     if cpt = 0 then (in0, out0, loc0)
     else 
       let aut = Sys.argv.(arg_nb-cpt) in
       let (i, o, l) = (Env.read_env_state aut) in
 	read_list_of_aut (cpt-1) 
-	  ((append i in0), (append o out0), (append l loc0))
+	  ((merge i in0), (merge o out0), (merge l loc0))
 and
   (main2 : int -> int -> 'a) =
   fun test_size thickness -> 
     let (env_in0, env_out0, env_loc0) = 
-      if (arg_nb = 0) then (failwith "lurette takes as argument a list of .aut files.\n")
+      if (arg_nb = 0) then 
+	(failwith "lurette takes as argument a list of .aut files.\n")
       else read_list_of_aut (arg_nb-1) ([], [], []) 
     in
     let env_in = sort_list_string_pair env_in0 in

lurette.mli

@@ -3,6 +3,5 @@
 open Env
 
 
-
 val main : int -> int -> unit
 

lurette.prj

 ;; -*- Prcs -*-
 (Created-By-Prcs-Version 1 3 3)
 (Project-Description "Lurette")
-(Project-Version lurette 0 12)
-(Parent-Version lurette 0 11)
+(Project-Version lurette 0 13)
+(Parent-Version lurette 0 12)
 (Version-Log "
-Add a version of sut_idl_stub.ml in interface for testing purposes.
+Just a few cosmetic changes.
 ")
 (New-Version-Log "")
-(Checkin-Time "Tue, 20 Nov 2001 14:37:37 +0100")
+(Checkin-Time "Thu, 22 Nov 2001 13:53:30 +0100")
 (Checkin-Login jahier)
 (Populate-Ignore ())
 (Project-Keywords)
@@ -18,20 +18,23 @@ Add a version of sut_idl_stub.ml in interface for testing purposes.
 
 
 ;; Sources files
-  (lurette.mli (lurette/11_lurette.ml 1.4 644))
-  (lurette.ml (lurette/12_lurette.ml 1.7 644))
+  (lurette.mli (lurette/11_lurette.ml 1.5 644))
+  (lurette.ml (lurette/12_lurette.ml 1.8 644))
 
   (graph.mli (lurette/13_graph.mli 1.2 644))
   (graph.ml (lurette/14_graph.ml 1.2 644))
 
-  (env.mli (lurette/15_env.mli 1.3 644))
-  (env.ml (lurette/16_env.ml 1.6 644))
+  (env.mli (lurette/15_env.mli 1.4 644))
+  (env.ml (lurette/16_env.ml 1.7 644))
+  (util.ml (lurette/35_util.ml 1.1 644))
 
-  (interface/gen_stubs.ml (lurette/24_generate_l 1.7 644))
+
+  (interface/util.ml (../util.ml) :symlink)
+  (interface/gen_stubs.ml (lurette/24_generate_l 1.8 644))
 
 ;; Make files
   (OcamlMakefile (lurette/17_OcamlMakef 1.2 644))
-  (Makefile (lurette/18_Makefile 1.6 644))
+  (Makefile (lurette/18_Makefile 1.7 644))
   (interface/Makefile (lurette/25_Makefile 1.4 644))
   (make_lurette (lurette/27_make_luret 1.3 744))
 
@@ -79,6 +82,12 @@ Add a version of sut_idl_stub.ml in interface for testing purposes.
   (Mercury/graph.m (lurette/7_graph.m 1.1 644))
 
 
+
+;; Files added by populate at Tue, 20 Nov 2001 14:43:30 +0100,
+;; to version 0.12(w), by jahier:
+
+  (tram_simple.h (lurette/36_tram_simpl 1.1 644))
+  (tram_simple.c (lurette/37_tram_simpl 1.1 644))
 )
 (Merge-Parents)
 (New-Merge-Parents)

tram_simple.c

+/********
+* ec2c version 0.4-beta
+* c file generated for node : tram_simple 
+********/
+#include <stdlib.h>
+#define _tram_simple_EC2C_SRC_FILE
+#include "tram_simple.h"
+/*--------
+Internal structure for the call
+--------*/
+typedef struct  {
+   void* client_data;
+   //INPUTS
+   _boolean _demande_porte;
+   _boolean _en_station;
+   _boolean _porte_ouverte;
+   _boolean _attention_depart;
+   //OUTPUTS
+   _boolean _fermer_porte;
+   _boolean _ouvrir_porte;
+   _boolean _porte_ok;
+   _boolean _attention_depart_a_retentit;
+   _boolean _depart;
+   _boolean _accepter_demande;
+   _boolean _porte_demandee;
+   _boolean _depart_imminent;
+   //REGISTERS
+   _boolean M38;
+   _boolean M38_nil;
+   _boolean M32;
+   _boolean M32_nil;
+   _boolean M22;
+   _boolean M22_nil;
+   _boolean M16;
+   _boolean M16_nil;
+   _boolean M12;
+   _boolean M12_nil;
+   _boolean M7;
+} tram_simple_ctx;
+/*--------
+Output procedures must be defined,
+Input procedures must be used:
+--------*/
+void tram_simple_I_demande_porte(tram_simple_ctx* ctx, _boolean V){
+   ctx->_demande_porte = V;
+}
+void tram_simple_I_en_station(tram_simple_ctx* ctx, _boolean V){
+   ctx->_en_station = V;
+}
+void tram_simple_I_porte_ouverte(tram_simple_ctx* ctx, _boolean V){
+   ctx->_porte_ouverte = V;
+}
+void tram_simple_I_attention_depart(tram_simple_ctx* ctx, _boolean V){
+   ctx->_attention_depart = V;
+}
+extern void tram_simple_O_fermer_porte(void*, _boolean);
+extern void tram_simple_O_ouvrir_porte(void*, _boolean);
+extern void tram_simple_O_porte_ok(void*, _boolean);
+extern void tram_simple_O_attention_depart_a_retentit(void*, _boolean);
+extern void tram_simple_O_depart(void*, _boolean);
+extern void tram_simple_O_accepter_demande(void*, _boolean);
+extern void tram_simple_O_porte_demandee(void*, _boolean);
+extern void tram_simple_O_depart_imminent(void*, _boolean);
+#ifdef CKCHECK
+extern void tram_simple_BOT_fermer_porte(void*);
+extern void tram_simple_BOT_ouvrir_porte(void*);
+extern void tram_simple_BOT_porte_ok(void*);
+extern void tram_simple_BOT_attention_depart_a_retentit(void*);
+extern void tram_simple_BOT_depart(void*);
+extern void tram_simple_BOT_accepter_demande(void*);
+extern void tram_simple_BOT_porte_demandee(void*);
+extern void tram_simple_BOT_depart_imminent(void*);
+#endif
+/*--------
+Internal reset input procedure
+--------*/
+static void tram_simple_reset_input(tram_simple_ctx* ctx){
+   //NOTHING FOR THIS VERSION...
+}
+/*--------
+Reset procedure
+--------*/
+void tram_simple_reset(tram_simple_ctx* ctx){
+   ctx->M38_nil = _true;
+   ctx->M32_nil = _true;
+   ctx->M22_nil = _true;
+   ctx->M16_nil = _true;
+   ctx->M12_nil = _true;
+   ctx->M7 = _true;
+   tram_simple_reset_input(ctx);
+}
+/*--------
+Dynamic allocation of an internal structure
+--------*/
+tram_simple_ctx* tram_simple_new_ctx(void* cdata){
+   tram_simple_ctx* ctx = (tram_simple_ctx*)calloc(1, sizeof(tram_simple_ctx));
+   ctx->client_data = cdata;
+   tram_simple_reset(ctx);
+   return ctx;
+}
+/*--------
+Copy the value of an internal structure
+--------*/
+void tram_simple_copy_ctx(tram_simple_ctx* dest, tram_simple_ctx* src){
+   memcpy((void*)dest, (void*)src, sizeof(tram_simple_ctx));
+}
+/*--------
+Step procedure
+--------*/
+void tram_simple_step(tram_simple_ctx* ctx){
+//LOCAL VARIABLES
+   _boolean L17;
+   _boolean L15;
+   _boolean L14;
+   _boolean L13;
+   _boolean L11;
+   _boolean L10;
+   _boolean L6;
+   _boolean L20;
+   _boolean L21;
+   _boolean L19;
+   _boolean L18;
+   _boolean L5;
+   _boolean L4;
+   _boolean L25;
+   _boolean L24;
+   _boolean L28;
+   _boolean L27;
+   _boolean L31;
+   _boolean L30;
+   _boolean L39;
+   _boolean L37;
+   _boolean L36;
+   _boolean L35;
+   _boolean T38;
+   _boolean T32;
+   _boolean T22;
+   _boolean T16;
+   _boolean T12;
+//CODE
+   L17 = (! ctx->_en_station);
+   L15 = (ctx->M16 && L17);
+   if (ctx->M7) {
+      L14 = _false;
+   } else {
+      L14 = L15;
+   }
+   L13 = (! L14);
+   L11 = (ctx->M12 && L13);
+   if (ctx->_attention_depart) {
+      L10 = _true;
+   } else {
+      L10 = L11;
+   }
+   if (ctx->M7) {
+      L6 = _false;
+   } else {
+      L6 = L10;
+   }
+   L20 = (! ctx->_porte_ouverte);
+   L21 = (ctx->M22 && L20);
+   if (ctx->_demande_porte) {
+      L19 = L20;
+   } else {
+      L19 = L21;
+   }
+   if (ctx->M7) {
+      L18 = _false;
+   } else {
+      L18 = L19;
+   }
+   L5 = (L6 && L18);
+   L4 = (L5 && ctx->_porte_ouverte);
+   tram_simple_O_fermer_porte(ctx->client_data, L4);
+   L25 = (ctx->_en_station && L18);
+   L24 = (L25 && L20);
+   tram_simple_O_ouvrir_porte(ctx->client_data, L24);
+   if (ctx->_demande_porte) {
+      L28 = L20;
+   } else {
+      L28 = _true;
+   }
+   L27 = (L6 && L28);
+   tram_simple_O_porte_ok(ctx->client_data, L27);
+   if (ctx->_attention_depart) {
+      L31 = _true;
+   } else {
+      L31 = ctx->M32;
+   }
+   if (ctx->M7) {
+      L30 = _false;
+   } else {
+      L30 = L31;
+   }
+   tram_simple_O_attention_depart_a_retentit(ctx->client_data, L30);
+   tram_simple_O_depart(ctx->client_data, L14);
+   L39 = (! ctx->_attention_depart);
+   L37 = (ctx->M38 && L39);
+   if (L14) {
+      L36 = _true;
+   } else {
+      L36 = L37;
+   }
+   if (ctx->M7) {
+      L35 = _true;
+   } else {
+      L35 = L36;
+   }
+   tram_simple_O_accepter_demande(ctx->client_data, L35);
+   tram_simple_O_porte_demandee(ctx->client_data, L18);
+   tram_simple_O_depart_imminent(ctx->client_data, L6);
+   T38 = L35;
+   T32 = L30;
+   T22 = L18;
+   T16 = ctx->_en_station;
+   T12 = L6;
+   ctx->M38 = T38;
+   ctx->M38_nil = _false;
+   ctx->M32 = T32;
+   ctx->M32_nil = _false;
+   ctx->M22 = T22;
+   ctx->M22_nil = _false;
+   ctx->M16 = T16;
+   ctx->M16_nil = _false;
+   ctx->M12 = T12;
+   ctx->M12_nil = _false;
+   ctx->M7 = ctx->M7 && !(_true);
+}

tram_simple.h

+/********
+* ec2c version 0.4-beta
+* c header file generated for node : tram_simple 
+* to be used with : tram_simple.c 
+********/
+/*-------- Predefined types ---------*/
+#ifndef _tram_simple_EC2C_PREDEF_TYPES
+#define _tram_simple_EC2C_PREDEF_TYPES
+typedef int _boolean;
+typedef int _integer;
+typedef char* _string;
+typedef double _real;
+typedef double _double;
+typedef float _float;
+#define _false 0
+#define _true 1
+#endif
+/*--------- Pragmas ----------------*/
+//MODULE: tram_simple 4 8
+//IN: _boolean demande_porte
+//IN: _boolean en_station
+//IN: _boolean porte_ouverte
+//IN: _boolean attention_depart
+//OUT: _boolean fermer_porte
+//OUT: _boolean ouvrir_porte
+//OUT: _boolean porte_ok
+//OUT: _boolean attention_depart_a_retentit
+//OUT: _boolean depart
+//OUT: _boolean accepter_demande
+//OUT: _boolean porte_demandee
+//OUT: _boolean depart_imminent
+#ifndef _tram_simple_EC2C_SRC_FILE
+/*--------Context type -------------*/
+struct tram_simple_ctx;
+/*--------Context allocation --------*/
+extern struct tram_simple_ctx* tram_simple_new_ctx(void* client_data);
+/*--------Context copy -------------*/
+extern void tram_simple_copy_ctx(struct tram_simple_ctx* dest, struct 
+tram_simple_ctx* src);
+/*-------- Reset procedure -----------*/
+extern void tram_simple_reset(struct tram_simple_ctx* ctx);
+/*-------- Step procedure -----------*/
+extern void tram_simple_step(struct tram_simple_ctx* ctx);
+/*-------- Input procedures -------------*/
+extern void tram_simple_I_demande_porte(struct tram_simple_ctx*, _boolean);
+extern void tram_simple_I_en_station(struct tram_simple_ctx*, _boolean);
+extern void tram_simple_I_porte_ouverte(struct tram_simple_ctx*, _boolean);
+extern void tram_simple_I_attention_depart(struct tram_simple_ctx*, _boolean);
+#endif

util.ml

+
+let rec (rm: 'a -> 'a list -> 'a list) =
+(* 
+** [rm x l] returns l without x. x should be in l. 
+*)
+  fun x l -> 
+    match l with
+	[] -> assert false
+      | y::t -> (if x = y then t else y::(rm x t))
+
+let rec (list_is_included: 'a list -> 'a list -> bool) = 
+(*  
+** [list_is_included l1 l2] tests if l1 is included into l2.
+*)
+  fun l1 l2 -> 
+    match l1 with
+	[] -> true
+      | (x1::t1) -> ( if (List.mem x1 l2) then 
+			list_is_included t1 (rm x1 l2)
+		      else
+			false )
+ 
+let (list_are_equals: 'a list -> 'a list -> bool) = 
+(*  
+** Tests if 2 lists are equals.
+*)
+  fun l1 l2 -> 
+    (list_is_included l1 l2 && list_is_included l2 l1)
+
+
+
+(* 
+** XXX to put in util.ml 
+*)
+let (readfile: string -> string) = 
+  fun file -> 
+     (* 
+     ** [readfile file] outputs the whole contents of the file `file' in a 
+     ** string.
+     *)
+    let rec (readfile_ic : in_channel -> string -> string) = 
+      fun ic acc ->
+	let line = try (input_line ic) with End_of_file -> (close_in ic) ; "end_of_file" in
+	  if (line = "end_of_file") then acc else (readfile_ic ic (acc ^ "\n" ^ line))
+    in 
+    let ic = (open_in file) in
+    let str = readfile_ic ic "" in
+      close_in ic;
+      str
+
+let rec (list_map3: ('a -> 'b -> 'c -> 'd) -> 'a list -> 'b list 
+	   -> 'c list -> 'd list) =
+  fun f l1 l2 l3 -> 
+    match (l1, l2, l3) with
+	([], [], []) -> []
+      | (e1::t1, e2::t2, e3::t3) -> 
+	  (f e1 e2 e3)::(list_map3 f t1 t2 t3)
+      | _ -> failwith ("*** Error: list_map3 should be called with lists "  
+		       ^ "of the same size.")
+
+let rec (list_map4: ('a -> 'b -> 'c -> 'd -> 'e) -> 'a list -> 'b list 
+	   -> 'c list -> 'd list -> 'e list) =
+  fun f l1 l2 l3 l4 -> 
+    match (l1, l2, l3, l4) with
+	([], [], [], []) -> []
+      | (e1::t1, e2::t2, e3::t3, e4::t4) -> 
+	  (f e1 e2 e3 e4)::(list_map4 f t1 t2 t3 t4)
+      | _ -> failwith ("*** Error: list_map3 should be called with lists "  
+		       ^ "of the same size.")
+	  
+(*
+** Sorts variables lexicographically w.r.t. to their names.
+*)
+let (sort_list_string_pair:  (string * string) list -> (string * string) list) =
+  fun var_list -> 
+    List.sort (fun (vn1, t1) (vn2, t2) -> compare vn1 vn2) var_list 
+
+
+(*
+** merges two lists without introducing duplicates.
+*)
+let rec (merge: 'a list -> 'a list -> 'a list) =
+  fun list1 list2 ->
+    match list1 with
+	[] -> list2
+      | x1::t1 -> 
+	  if (List.mem x1 list2)
+	  then  merge t1 list2
+	  else merge t1 (x1::list2)
+
+
+
+(* 
+ ** [readfile file] outputs the whole contents of the file `file' in a 
+ ** string.
+ *)
+let (readfile: string -> string) = 
+  let rec (readfile_ic : in_channel -> string -> string) = 
+    fun ic acc ->
+      let line = try (input_line ic) with End_of_file -> (close_in ic) ; "end_of_file" in
+	if (line = "end_of_file") then acc else (readfile_ic ic (acc ^ line))
+  in
+    fun file -> readfile_ic (open_in file) ""
+