diff --git a/src/syntaxTreeCore.ml b/src/syntaxTreeCore.ml
index 48906f86139beb2e8ae1d28ef75481c30bd56fef..982e9f5f190915fa3fd85b2b9ba1f58beaa323f2 100644
--- a/src/syntaxTreeCore.ml
+++ b/src/syntaxTreeCore.ml
@@ -1,4 +1,4 @@
-(** Time-stamp: <modified the 20/02/2008 (at 13:35) by Erwan Jahier> *)
+(** Time-stamp: <modified the 06/03/2008 (at 14:56) by Erwan Jahier> *)
 
 
 (** (Raw) Abstract syntax tree of source programs. *)
@@ -91,7 +91,6 @@ and slice_info = {
 
 and predef_node =
 (* zeroaire *)
-    NULL_exp
   | TRUE_n
   | FALSE_n
   | ICONST_n of Ident.t
@@ -180,7 +179,7 @@ and by_name_op =
   | STRUCT_anonymous_n
       (* for backward compatibility with lv4 *)
 
-and node_exp =
+and node_exp = 
   | CallPreDef of predef_node
   | CallUsrDef of (Ident.idref * static_arg srcflagged list)
       (*
diff --git a/src/syntaxTreeDump.ml b/src/syntaxTreeDump.ml
index 2c4c7d1cfdd1f09378d19ef6146eabafc5bd4e06..82570b2a009ce67994c24fce748cc52df073718e 100644
--- a/src/syntaxTreeDump.ml
+++ b/src/syntaxTreeDump.ml
@@ -1,4 +1,4 @@
-(** Time-stamp: <modified the 20/02/2008 (at 13:36) by Erwan Jahier> *)
+(** Time-stamp: <modified the 06/03/2008 (at 14:42) by Erwan Jahier> *)
 
 
 open Lxm
@@ -48,7 +48,6 @@ let (op2string : SyntaxTreeCore.predef_node -> string) =
     | (REAL2INT_n)-> assert false
     | (FALSE_n  ) -> assert false
     | (TRUE_n   ) -> assert false
-    | (NULL_exp ) -> assert false
 	(* ternaires *)
     | (IF_n     ) -> "if"
     | (WITH_n   ) -> "with" 
@@ -463,7 +462,6 @@ and dump_by_pos_exp (os: Format.formatter) (oper: predef_node) (pars: operands)
 
       | (FBY_n, _) -> assert false
       | (PROJ_n _, _) -> assert false
-      | (NULL_exp, _) -> assert false
 
       | (STRUCT_ACCESS_n _, _) -> assert false
       | (ARRAY_SLICE_n _, _) -> assert false
diff --git a/src/test/test.res.exp b/src/test/test.res.exp
index 5abe196dd5f5a7a4a7c8d2b43913bea3a80a3e06..bafc9738c23cca3e455a7adb5a1651549f9174b3 100644
--- a/src/test/test.res.exp
+++ b/src/test/test.res.exp
@@ -1440,31 +1440,6 @@ End of Syntax table dump. 
 		node dummy::bad_call02 = dummy::bad_call02(int, bool) returns (int) on clock XXX
 
 *** SyntaxTab.create pass 1
-*** SyntaxTab.create pass 2
-    init pack dummy
-       export node titi
-       export node call02
-       export node toto
-*** SyntaxTab.create pass 3
-   init symbol tables for pack dummy
-*** SyntaxTab.create done
-*** « Syntax table dump:
- 	 - Package or model list:
-		call02 (pack) 
-		
-	 - Raw model table: 
-	 - Raw Package table: dummy 
-	 - Package manager table: dummy 
-End of Syntax table dump. »
--- MAIN NODE: "call02::main"
-*** Dump the exported items of the packages.
- * package dummy
-	Exported types:
-	Exported constants:
-*** Error in file "should_work/call/call02.lus", line 2, col 13 to 23, token 'Lustre::and': unknown node
-
-	Exported nodes:
-*** SyntaxTab.create pass 1
 *** SyntaxTab.create pass 2
     init pack dummy
        export node call07
@@ -1594,6 +1569,31 @@ End of Syntax table dump. 
 
 		node dummy::bip = extern bip(bool, bool) returns (bool, bool)
 
+*** SyntaxTab.create pass 1
+*** SyntaxTab.create pass 2
+    init pack dummy
+       export node titi
+       export node call02
+       export node toto
+*** SyntaxTab.create pass 3
+   init symbol tables for pack dummy
+*** SyntaxTab.create done
+*** « Syntax table dump:
+ 	 - Package or model list:
+		call02 (pack) 
+		
+	 - Raw model table: 
+	 - Raw Package table: dummy 
+	 - Package manager table: dummy 
+End of Syntax table dump. »
+-- MAIN NODE: "call02::main"
+*** Dump the exported items of the packages.
+ * package dummy
+	Exported types:
+	Exported constants:
+*** Error in file "should_work/call/call02.lus", line 2, col 13 to 23, token 'Lustre::and': unknown node
+
+	Exported nodes:
 *** Error in file "should_work/packEnvTest/contractForElementSelectionInArray/main.lus", line 3, col 45 to 45, token '=': syntax error
 
 *** SyntaxTab.create pass 1
@@ -5008,7 +5008,7 @@ End of Syntax table dump. 
 		type Int8::Int = Int8::Int
 	Exported constants:
 Int8::n = 8 can be provided.
-*** oops: an internal error occurred in file lazyCompiler.ml, line 318, column 5
+*** oops: an internal error occurred in file lazyCompiler.ml, line 330, column 5
 *** when compiling lustre program should_work/NONREG/Int.lus
 *** SyntaxTab.create pass 1
 *** SyntaxTab.create pass 2
@@ -5558,68 +5558,64 @@ End of Syntax table dump. 
 *** SyntaxTab.create pass 1
 *** SyntaxTab.create pass 2
     init pack dummy
-       export type t2
-       export type t
-       export const m
-       export const n
-       export const o
-       export const s
-       export node tranche
+       export type pendule
+       export const G
+       export const L
+       export const T
+       export node jeu
+       export node make_pend
+       export node sqrt
+       export node cos
+       export node D
+       export node sin
+       export node asservi
+       export node I
+       export node PEND
+       export node I2
 *** SyntaxTab.create pass 3
    init symbol tables for pack dummy
 *** SyntaxTab.create done
 *** « Syntax table dump:
  	 - Package or model list:
-		tranche (pack) 
+		asservi (pack) 
 		
 	 - Raw model table: 
 	 - Raw Package table: dummy 
 	 - Package manager table: dummy 
 End of Syntax table dump. »
--- MAIN NODE: "tranche::main"
+-- MAIN NODE: "asservi::main"
 *** Dump the exported items of the packages.
  * package dummy
 	Exported types:
-		type dummy::t2 = bool^7^8^9^10
-		type dummy::t = bool^3^4
-*** Error in file "should_work/demo/tranche.lus", line 7, col 6 to 6, token 'n': can't eval constant: external constant not allowed (in file "should_work/demo/tranche.lus", line 7, col 6 to 6, token 'n')
-
+		type dummy::pendule = dummy::pendule
 	Exported constants:
-*** Error in file "should_work/to_sort_out/record.lus", line 2, col 2 to 7, token 'struct': syntax error
+		const dummy::G = 10.000000
+		const dummy::L = 2.000000
+		const dummy::T = 0.100000
+	Exported nodes:
+		node dummy::jeu = dummy::jeu(real, real) returns (dummy::pendule) on clock XXX
 
-*** Error in file "should_work/to_sort_out/asservi.lus", line 7, col 1 to 8, token 'function': syntax error
+		node dummy::make_pend = extern make_pend(real, real, real, real) returns (dummy::pendule)
 
-*** Error in file "should_work/to_sort_out/const2.lus", line 10, col 11 to 11, token 'M': unknown constant
+		node dummy::sqrt = extern sqrt(real) returns (real)
+
+		node dummy::cos = extern cos(real) returns (real)
+
+		node dummy::D = dummy::D(real) returns (real) on clock XXX
+
+		node dummy::sin = extern sin(real) returns (real)
+
+		node dummy::asservi = dummy::asservi(real) returns (dummy::pendule) on clock XXX
+
+		node dummy::I = dummy::I(real) returns (real) on clock XXX
+
+		node dummy::PEND = dummy::PEND(real, real) returns (real) on clock XXX
+
+		node dummy::I2 = dummy::I2(real) returns (real) on clock XXX
 
-*** SyntaxTab.create pass 1
-*** SyntaxTab.create pass 2
-    init pack dummy
-       export type t1
-       export type t2
-       export type t3
-       export type t4
-       export type t5
-       export type t6
-       export type t7
-       export type t8
-       export const e3
-*** SyntaxTab.create pass 3
-   init symbol tables for pack dummy
-*** SyntaxTab.create done
-*** « Syntax table dump:
- 	 - Package or model list:
-		const2 (pack) 
-		
-	 - Raw model table: 
-	 - Raw Package table: dummy 
-	 - Package manager table: dummy 
-End of Syntax table dump. »
--- MAIN NODE: "const2::main"
-*** Dump the exported items of the packages.
- * package dummy
-	Exported types:
-		type dummy::t1 = int
 Those tests are supposed to generate errors
+*** Error in file "should_fail/syntax/record.lus", line 7, col 29 to 29, token '{': syntax error
+
 *** SyntaxTab.create pass 1
 *** SyntaxTab.create pass 2
     init pack dummy
@@ -5876,6 +5872,80 @@ End of Syntax table dump. 
 	Exported nodes:
 *** Error in file "should_fail/semantics/bad_call03.lus", line 2, col 18 to 18, token '+': syntax error
 
+*** SyntaxTab.create pass 1
+*** SyntaxTab.create pass 2
+    init pack dummy
+       export type t2
+       export type t
+       export const m
+       export const n
+       export const o
+       export const s
+       export node tranche
+*** SyntaxTab.create pass 3
+   init symbol tables for pack dummy
+*** SyntaxTab.create done
+*** « Syntax table dump:
+ 	 - Package or model list:
+		tranche (pack) 
+		
+	 - Raw model table: 
+	 - Raw Package table: dummy 
+	 - Package manager table: dummy 
+End of Syntax table dump. »
+-- MAIN NODE: "tranche::main"
+*** Dump the exported items of the packages.
+ * package dummy
+	Exported types:
+		type dummy::t2 = bool^7^8^9^10
+		type dummy::t = bool^3^4
+*** Error in file "should_fail/semantics/tranche.lus", line 7, col 6 to 6, token 'n': can't eval constant: external constant not allowed (in file "should_fail/semantics/tranche.lus", line 7, col 6 to 6, token 'n')
+
+	Exported constants:
+*** SyntaxTab.create pass 1
+*** SyntaxTab.create pass 2
+    init pack dummy
+       export type t1
+       export type t2
+       export type t3
+       export type t4
+       export type t5
+       export type t6
+       export type t7
+       export type t8
+       export const c10
+       export const e3
+       export const M
+       export const N
+       export const O
+       export const P
+*** SyntaxTab.create pass 3
+   init symbol tables for pack dummy
+*** SyntaxTab.create done
+*** « Syntax table dump:
+ 	 - Package or model list:
+		const2 (pack) 
+		
+	 - Raw model table: 
+	 - Raw Package table: dummy 
+	 - Package manager table: dummy 
+End of Syntax table dump. »
+-- MAIN NODE: "const2::main"
+*** Dump the exported items of the packages.
+ * package dummy
+	Exported types:
+		type dummy::t1 = int
+		type dummy::t2 = int^3
+		type dummy::t3 = int^3^6
+		type dummy::t4 = int^3^6^3
+		type dummy::t5 = int^3^6^3^2
+		type dummy::t6 = int^3^6^3^2^12
+		type dummy::t7 = int^3^6^3^2^12^3
+		type dummy::t8 = int^3^6^3^2^12^3^3
+*** Error in file "should_fail/semantics/const2.lus", line 4, col 13 to 16, token 'when': can't eval constant: operation when not allowed in static expression
+
+	Exported constants:
+		const dummy::c10 = 12
 *** Error in file "should_fail/clock/clock.lus", line 6, col 1 to 4, token 'node': syntax error
 
 *** Error in file "should_fail/type/Gyro.lus", line 11, col 42 to 42, token ',': syntax error