fixer parser when there is no args

src/main/antlr/VSLParser.g

@@ -31,10 +31,9 @@ liste_param returns [ArrayList<VarImp> out]
   @init{
     $out = new ArrayList<VarImp>();
   }: 
-    (
-      (ii1=ident {$out.add(new VarImp($ii1.out));})
+      ii1=ident {$out.add(new VarImp($ii1.out));}
       (VIRGULE ii2=ident  {$out.add(new VarImp($ii2.out));})*
-    )*
+    
   ; 
 
 functions returns [ArrayList<Function> out]
@@ -221,7 +220,7 @@ lit  returns [Expression out]:
     }
     | t=ident
       ( 
-        ParO (para=list_expression)? ParF {$out = new AppealImp($t.out,$para.out);}
+        ParO (para=list_expression)? ParF {$out = new AppealImp($t.out,($para.out !=null) ?$para.out : new ArrayList<>());}
         | {$out=new VarImp($t.out);}
       )
   ;