diff --git a/include/assoc.cpp b/include/assoc.cpp
index 0d5b3d267..17c2132cb 100755
--- a/include/assoc.cpp
+++ b/include/assoc.cpp
@@ -239,9 +239,10 @@ TObject* TAssoc_array::objptr(
 // @flag FALSE | Se la chiave non esiste
 bool TAssoc_array::is_key(
   const char* key) const // @parm Chiave da cercarne l'esistenza
-
 { 
-  return objptr(key) != NULL;
+  bool isnew = FALSE; 
+  THash_object* o = ((TAssoc_array *)this)->_lookup(key,isnew);
+  return o != NULL;
 }
 
 // @doc EXTERNAL
diff --git a/include/assoc.h b/include/assoc.h
index 7f759b8f1..d56364b0a 100755
--- a/include/assoc.h
+++ b/include/assoc.h
@@ -35,8 +35,8 @@ public:
   TObject& obj() const
   { return *_obj; }
 
-  // @cmember Costruttore (inizializza la chiave)
-  THash_object(const char* k) : _key(k), _obj(NULL)
+  // @cmember Costruttore (inizializza la chiave ed opzionalmente l'oggetto)
+  THash_object(const char* k, TObject* o = NULL) : _key(k), _obj(o)
   {}
   // @cmember Distruttore
   ~THash_object()
diff --git a/include/expr.cpp b/include/expr.cpp
index 3099fc7f9..f9889b083 100755
--- a/include/expr.cpp
+++ b/include/expr.cpp
@@ -1,4 +1,5 @@
 #include <ctype.h>
+#include <stdio.h>
 #include <stdlib.h>
 
 #define __EXPR_CPP
@@ -126,6 +127,58 @@ const char* TVararray::getstring(int varnum)
   const TVar* var = (const TVar*)objptr(varnum);
   CHECKD(var, "Variabile nulla: ", varnum);
   return var->string();
+}           
+
+///////////////////////////////////////////////////////////
+// TEval_stack
+///////////////////////////////////////////////////////////
+
+real& TEval_stack::pop_real()
+{          
+  TObject& o = pop();
+  if (o.class_id() == CLASS_STRING)
+  { 
+    real* r = new real((TString&)o);
+    push(r);
+    return (real&)pop();  
+  }
+  return (real&)o;
+}
+
+real& TEval_stack::peek_real()
+{          
+  TObject& o = peek(0);
+  if (o.class_id() == CLASS_STRING)
+  {                  
+    pop(); 
+    real* r = new real((TString&)o);
+    push(r);
+    return *r;  
+  }
+  return (real&)o;
+}
+
+TString& TEval_stack::pop_string()
+{          
+  TObject& o = pop();
+  if (o.class_id() == CLASS_STRING)
+    return (TString&)o;  
+
+  TString* s = new TString(((real&)o).string());
+  push(s);
+  return (TString&)pop();
+}
+
+TString& TEval_stack::peek_string()
+{          
+  TObject& o = peek();
+  if (o.class_id() == CLASS_STRING)
+    return (TString&)o;  
+  
+  pop();  
+  TString* s = new TString(((real&)o).string());
+  push(s);
+  return *s;
 }
 
 
@@ -134,13 +187,13 @@ const char* TVararray::getstring(int varnum)
 ///////////////////////////////////////////////////////////
 
 TExpression::TExpression(const char* expression, TTypeexp type)
-: _original(expression)
+           : _original(expression)
 
 {
   _val = real(0.0);
   _dirty = TRUE;
   _type = type;
-  if (!compile(expression, type))
+  if (!compile(_original, type))
   {
     error_box("Wrong expression : %s", expression);
     _code.clear();
@@ -149,8 +202,7 @@ TExpression::TExpression(const char* expression, TTypeexp type)
 
 
 TExpression::TExpression(TTypeexp type)
-: _original("")
-
+           : _original("")
 {
   _val = real(0.0);
   _dirty = FALSE;
@@ -162,7 +214,6 @@ TExpression::TExpression(const TExpression & expr)
            : _code(expr._code), _var(expr._var), 
              _val(expr._val), _dirty(expr._dirty), 
              _type(expr._type), _original(expr._original)
-
 {
 }
 
@@ -173,7 +224,6 @@ TObject* TExpression::dup() const
 }    
 
 TExpression::operator const real&()
-
 {            
   if (user_func_dirty() || _dirty) eval();
   _dirty = FALSE;
@@ -182,20 +232,25 @@ TExpression::operator const real&()
 
 
 TExpression::operator const char*()
-
 {
   if (user_func_dirty() || _dirty) eval();
   _dirty = FALSE;
   return _val.string();
 }
 
+TExpression::operator bool()
+{
+  if (user_func_dirty() || _dirty) eval();
+  _dirty = FALSE;
+  return !_val.number().is_zero();          
+}
 
 void TExpression::print_on(ostream& out) const       
 { out << _original; }
 
-void TExpression::evaluate_user_func(int index, int nparms, TStack & stack, TTypeexp  type) const
+void TExpression::evaluate_user_func(int index, int nparms, TEval_stack& stack, TTypeexp  curtype) const
 {                
-  CHECKD(FALSE, "Unknown function ", index);
+  NFCHECK("Unknown function %d.", index);
   for ( int i = nparms ; i > 0; i--)
     stack.pop(); 
   if (curtype == _numexpr)  
@@ -204,15 +259,6 @@ void TExpression::evaluate_user_func(int index, int nparms, TStack & stack, TTyp
     stack.push(TString(""));
 }    
 
-TExpression::operator bool()
-
-{
-  if (user_func_dirty() || _dirty) eval();
-  _dirty = FALSE;
-  return !_val.number().is_zero();          
-}
-
-
 void TExpression::setvar(const char* varname, const real& val)
 
 {
@@ -261,12 +307,12 @@ bool TExpression::print_error(const char* msg) const
 
 void TExpression::eval()
 {                                   
-  TStack        evalstack(50);
-  TBit_array    types;
-  int           type_pointer = 0;
-  TCode         instr;
-  real          o1, o2;
-  TString       s1, s2;
+  TEval_stack evalstack;
+  TBit_array  types;
+  int         type_pointer = 0;
+  TCode       instr;
+  real        o1, o2;
+  TString     s1, s2;
     
   types.set(type_pointer, (_type == _numexpr));
   
@@ -303,161 +349,171 @@ void TExpression::eval()
       break;
     case _plus:                    
       if (type == _strexpr)
-      {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+      {  
+/*      
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         s1 << s2;
         evalstack.push(s1);
+*/                
+        // Non unire le seguenti righe
+        const TString& s = evalstack.pop_string();
+        evalstack.peek_string() << s;
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+/*      
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real(o1 + o2));
+*/        
+        // Non unire le seguenti righe
+        const real& r = evalstack.pop_real();
+        evalstack.peek_real() += r;
       }
       break;
     case _minus:
-      o2 = (real&) evalstack.pop();
-      o1 = (real&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      o1 = evalstack.pop_real();
       evalstack.push(real(o1 - o2));
       break;
     case _multiply:
-      o2 = (real&) evalstack.pop();
-      o1 = (real&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      o1 = evalstack.pop_real();
       evalstack.push(real(o1 * o2));
       break;
     case _divide:
-      o2 = (real&) evalstack.pop();
+      o2 = evalstack.pop_real();
       if (o2.is_zero())
       {
         print_error("Divisione per zero!");
         o2 = 1.0;
       }
-      o1 = (real&) evalstack.pop();
+      o1 = evalstack.pop_real();
       evalstack.push(real(o1 / o2));
       break;
     case _chgs:
-      o1 = (real&) evalstack.pop();
+      o1 = evalstack.pop_real();
       evalstack.push(-o1);
       break;
     case _and:
       if (type == _strexpr)
       {
-        o2 = real((const char*)(TString&)evalstack.pop());
-        o1 = real((const char*)(TString&)evalstack.pop());
+        o2 = real((const char*)evalstack.pop_string());
+        o1 = real((const char*)evalstack.pop_string());
         evalstack.push(TString((o1 != ZERO && o2 != ZERO) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 != ZERO && o2 != ZERO) ? 1.0 : 0.0));
       }
       break;
     case _or:
       if (type == _strexpr)
       {
-        o2 = real((const char*) (TString&)evalstack.pop());
-        o1 = real((const char*) (TString&)evalstack.pop());
+        o2 = real((const char*) evalstack.pop_string());
+        o1 = real((const char*) evalstack.pop_string());
         evalstack.push(TString((o1 != ZERO || o2 != ZERO) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 != ZERO || o2 != ZERO) ? 1.0 : 0.0));
       }
       break;
     case _not:
-      o1 = (real&) evalstack.pop();
+      o1 = evalstack.pop_real();
       evalstack.push(real((o1 == ZERO) ? 1.0 : 0.0));
       break;
     case _equal:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop(); 
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string(); 
         evalstack.push(TString((s1 == s2) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 == o2) ? 1.0 : 0.0));
       }
       break;
     case _match:
-      s2 = (TString&) evalstack.pop();
-      s1 = (TString&) evalstack.pop(); 
+      s2 = evalstack.pop_string();
+      s1 = evalstack.pop_string(); 
       evalstack.push(TString((s1.match(s2)) ? "1" : "0"));
       break;
     case _noteq:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         evalstack.push(TString(s1 != s2 ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 != o2) ? 1.0 : 0.0));
       }
       break;
     case _lt:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         evalstack.push(TString((s1 < (const char*)s2) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 < o2) ? 1.0 : 0.0));
       }
       break;
     case _gt:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         evalstack.push(TString((s1 > (const char*)s2) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 > o2) ? 1.0 : 0.0));
       }
       break;
     case _lteq:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         evalstack.push(TString((s1 <= (const char*)s2) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 <= o2) ? 1.0 : 0.0));
       }
       break;
     case _gteq:
       if (type == _strexpr)
       {
-        s2 = (TString&) evalstack.pop();
-        s1 = (TString&) evalstack.pop();
+        s2 = evalstack.pop_string();
+        s1 = evalstack.pop_string();
         evalstack.push(TString((s1 >= (const char*)s2) ? "1" : "0"));
       }
       else
       {
-        o2 = (real&) evalstack.pop();
-        o1 = (real&) evalstack.pop();
+        o2 = evalstack.pop_real();
+        o1 = evalstack.pop_real();
         evalstack.push(real((o1 >= o2) ? 1.0 : 0.0));
       }
       break;  
@@ -470,41 +526,41 @@ void TExpression::eval()
       }
       break;
     case _sqrt:
-      evalstack.push(real(sqrt((real&) evalstack.pop())));
+      evalstack.push(real(sqrt(evalstack.pop_real())));
       break;
     case _sqr:
-      evalstack.push(real(sqr((real&) evalstack.pop())));
+      evalstack.push(real(sqr(evalstack.pop_real())));
       break;
     case _exp10:
-      evalstack.push(real(exp10((real&) evalstack.pop())));
+      evalstack.push(real(exp10(evalstack.pop_real())));
       break;
     case _exp:
-      evalstack.push(real(exp((real&) evalstack.pop())));
+      evalstack.push(real(exp(evalstack.pop_real())));
       break;
     case _log10:
-      evalstack.push(real(log10((real&) evalstack.pop())));
+      evalstack.push(real(log10(evalstack.pop_real())));
       break;
     case _log:
-      evalstack.push(real(log((real&) evalstack.pop())));
+      evalstack.push(real(log(evalstack.pop_real())));
       break;
     case _sin:
-      evalstack.push(real(sin((real&) evalstack.pop())));
+      evalstack.push(real(sin(evalstack.pop_real())));
       break;
     case _cos:
-      evalstack.push(real(cos((real&) evalstack.pop())));
+      evalstack.push(real(cos(evalstack.pop_real())));
       break;
     case _tan:
-      evalstack.push(real(tan((real&) evalstack.pop())));
+      evalstack.push(real(tan(evalstack.pop_real())));
       break;
     case _left:
-      o2 = (real&) evalstack.pop();
-      s2 = (TString&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      s2 = evalstack.pop_string();
       s1 = s2.left((int)o2.integer());
       evalstack.push(s1);
       break;
     case _right:
-      o2 = (real&) evalstack.pop();
-      s2 = (TString&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      s2 = evalstack.pop_string();
       s1 = s2.right((int)o2.integer());
       evalstack.push(s1);
       break;
@@ -512,7 +568,8 @@ void TExpression::eval()
     {
       int count = (int)((const real&)evalstack.pop()).integer();   
       if (count == 0) count--;
-      const int from = (int)((const real&)evalstack.pop()).integer() - 1; 
+      int from = (int)((const real&)evalstack.pop()).integer() - 1; 
+      if (from < 0) from = 0;
       const TString& s = ((const TString&)evalstack.pop()).mid(from, count);
       evalstack.push(s);
     }  
@@ -520,59 +577,63 @@ void TExpression::eval()
     case _substr:
     {
       const int to = (int)((const real&)evalstack.pop()).integer();   
-      const int from = (int)((const real&)evalstack.pop()).integer() - 1; 
+      int from = (int)((const real&)evalstack.pop()).integer() - 1; 
+      if (from < 0) from = 0;
       const TString& s = ((const TString&)evalstack.pop()).sub(from, to);
       evalstack.push(s);
     }  
       break;
     case _pow:
-      o2 = (real&) evalstack.pop();
-      o1 = (real&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      o1 = evalstack.pop_real();
       evalstack.push(real(pow(o1, o2)));
       break;
     case _min:
       o2 = (real&)evalstack.pop();
       o1 = (real&)evalstack.pop();
-      evalstack.push(real(fnc_min(o1, o2)));
+      evalstack.push(o1 < o2 ? o1 : o2);
       break;
     case _max:
-      o2 = (real&) evalstack.pop();
-      o1 = (real&) evalstack.pop();
-      evalstack.push(real(fnc_max(o1, o2)));
+      o2 = evalstack.pop_real();
+      o1 = evalstack.pop_real();
+      evalstack.push(o1 > o2 ? o1 : o2);
       break;
     case _upper:
-      s1 = (TString&) evalstack.pop();
+/*    
+      s1 = evalstack.pop_string();
       s1.upper();
       evalstack.push(s1);
+*/
+      evalstack.peek_string().upper();
       break;
     case _round:
     {
-      const int ndec = (int)((real&) evalstack.pop()).integer();
-      o1 = (real&) evalstack.pop();
+      const int ndec = (int)(evalstack.pop_real()).integer();
+      o1 = evalstack.pop_real();
       o1.round(ndec);
       evalstack.push(o1);
     }
       break;
     case _trunc:
     {
-      const int ndec = (int)((real&) evalstack.pop()).integer();
-      o1 = (real&) evalstack.pop();
+      const int ndec = (int)(evalstack.pop_real()).integer();
+      o1 = evalstack.pop_real();
       o1.trunc(ndec);
       evalstack.push(o1);
     }
       break;
     case _ceil:
     {
-      const int ndec = (int)((real&) evalstack.pop()).integer();
-      o1 = (real&) evalstack.pop();
+      const int ndec = (int)(evalstack.pop_real()).integer();
+      o1 = evalstack.pop_real();
       o1.ceil(ndec);
       evalstack.push(o1);
     }
       break;
     case _perc:
     {
-      o2 = (real&) evalstack.pop();
-      o1 = (real&) evalstack.pop();
+      o2 = evalstack.pop_real();
+      o1 = evalstack.pop_real();
       const real val = real(o1 * o2 / 100.0);
       evalstack.push(val);
     }
@@ -589,16 +650,16 @@ void TExpression::eval()
     {     
       if (type == _strexpr)
       {
-        s1 = (TString&)evalstack.pop();
-        s2 = (TString&)evalstack.pop();
-        const real cond = (real) (TString&) evalstack.pop();;
+        s1 = evalstack.pop_string();
+        s2 = evalstack.pop_string();
+        const real cond(evalstack.pop_string());
         evalstack.push(cond.is_zero() ? s1 : s2);
       }
       else
       {
         o1 = (real&)evalstack.pop();
         o2 = (real&)evalstack.pop();
-        const real cond = (real&) evalstack.pop();;
+        const real cond = (real&)evalstack.pop();
         evalstack.push(cond.is_zero() ? o1 : o2);
       }
     }
@@ -636,11 +697,17 @@ void TExpression::eval()
       break;
     }
   }
-
-  if (_type == _strexpr)
-    _val = (TString&)evalstack.pop();
+  
+  // L'espressione non e' vuota
+  if (_code.items() > 1)
+  {
+    if (_type == _strexpr)
+      _val = evalstack.pop_string();
+    else
+      _val = evalstack.pop_real();
+  }
   else
-    _val = (real&)evalstack.pop();
+    _val = ZERO;    
 }
 
 
@@ -667,42 +734,49 @@ TCodesym TExpression::tok2fun(const char* tok) const
   int f = 0, l = MAX_TOK-1, i;                    
   while (TRUE)
   {
-    i = (f+l)>>1;                          
+//    i = (f+l)>>1;                          
+    i = (toupper(*tok) - *fnstr[f]) * (l-f+1) / (*fnstr[l] - *fnstr[f] + 1);
+    if (i < f || i > l)
+      return _invalid;
+    
     const int cmp = stricmp(tok, fnstr[i]);
     if (cmp == 0) 
       break;
     if (cmp > 0) f = i+1;
     else         l = i-1;
+    
     if (f > l) 
-    {
-      i = -1;
-      break;
-    }  
-  }
-  return i >= 0 ? fntok[i] : _invalid;
+      return _invalid;
+  }      
+  CHECKD(i >= 0 && i < MAX_TOK, "Invalid function index ", i);
+  return fntok[i];
 }
 
                                   
 
-TCodesym TExpression::__gettoken(bool reduct)
+TCodesym TExpression::__gettoken(bool /* reduct */)
 {
   TCodesym sym = _invalid;
-  int                           i = 0;
+  int i = 0;
   
   _tok[0] = '\0';
   while (isspace(*_s)) _s++;
   if (!*_s) return _endsym;
+
+/*  
   if ((reduct) && (*_s == ','))
   {
     _s++;
     return _comma;
   }
-  if (isdigit(*_s) || (*_s == '.') || (*_s == ','))
+*/  
+  
+  if (isdigit(*_s) || (*_s == '.') /* || (*_s == ',') */)
   {
     sym = _number;
-    while (isalpha(*_s) || isdigit(*_s) || (*_s == '-') || (*_s == '[') ||
+    while (isalnum(*_s) || (*_s == '-') || (*_s == '[') ||
            (*_s == ']') || (*_s == '.') || (*_s == ':')  || 
-           (!reduct && (*_s == ',')))
+           (*_s == '_') || (sym == _variable && (*_s == ',')))
     {
       if (*_s == '-')
       {
@@ -714,19 +788,22 @@ TCodesym TExpression::__gettoken(bool reduct)
       else 
       {   
         if (sym == _number)
-          if ((isalpha(*_s)) ||(*_s == '[') || (*_s == ']') ||
-              (*_s == ',') || (*_s == ':')) sym = _variable;
+        {
+          if (isalpha(*_s) || (*_s == '[') || (*_s == ']') ||
+              (*_s == ',') || (*_s == ':') || (*_s == '_')) 
+            sym = _variable;
+        }    
         _tok[i++] = *(_s++);
       } 
     } 
     _tok[i] = '\0';
     return sym;
   }
-  if (isalpha(*_s) || (*_s == '#'))
+  if (isalpha(*_s) || (*_s == '#') || (*_s == '_'))
   {
     _tok[i++] = *(_s++);
-    while (isalpha(*_s) || isdigit(*_s) || (*_s == '-') || (*_s == '[') ||
-           (*_s == ']') || (*_s == ':') || (!reduct && (*_s == ',')))
+    while (isalnum(*_s) || (*_s == '-') || (*_s == '[') ||
+           (*_s == ']') || (*_s == ':') || (*_s == ',') || (*_s == '_'))
     {
       if (*_s == '-')
       {
@@ -760,7 +837,8 @@ TCodesym TExpression::__gettoken(bool reduct)
       return _string;
     }
   case ',' :
-    _s++;
+    _tok[i++] = *(_s++);
+    _tok[i] = '\0';
     return _comma;
   case '(' :
     _tok[i++] = *(_s++);
@@ -854,18 +932,38 @@ TCodesym TExpression::__factor(TCodesym startsym)
   case _lpar:
     sym = __gettoken();
     sym = __expression(sym);
-    if (sym == _rpar) sym = __gettoken();
+    if (sym == _rpar) sym = __gettoken(); 
+    else sym = _invalid;
     break;
   case _variable:
+    {     
+      int from = 1, to = 0;
+      char* quadra = strchr(_tok, '[');
+      if (quadra)
+      {
+        if (sscanf(quadra, "[%d,%d]", &from, &to) == 0)
+        {
+          sym = _invalid;
+          break;
+        }
+        *quadra = '\0';
+      }                        
+      _code.add(_variable, _tok);
+      if (quadra)
+      {
+        _code.add(_number, real(from));
+        _code.add(_number, real(to > from ? to-from+1 : 0));
+        _code.add(_mid);
+      }  
+      for (int i = numvar()-1 ; i >= 0; i--)
+        if (strcmp(_tok, varname(i)) == 0) break;
+      if (i < 0) _var.add(_tok);
+      sym = __gettoken(TRUE);
+    }
+    break;
   case _number:
   case _string:
     _code.add(startsym, _tok);
-    if (startsym == _variable)
-    {
-      for (int i = 0 ; i < numvar(); i++)
-        if (strcmp(_tok, varname(i)) == 0) break;
-      if (i == numvar()) _var.add(_tok);
-    }
     sym = __gettoken(TRUE);
     break;  
   case _userfunc:
@@ -901,6 +999,8 @@ TCodesym TExpression::__factor(TCodesym startsym)
             sym = __gettoken(TRUE);
           }  
         }
+        else
+          sym = _invalid;
       }
     }
     break;  
@@ -926,8 +1026,7 @@ TCodesym TExpression::__factor(TCodesym startsym)
     sym = __gettoken();
     if (sym == _lpar) sym = __gettoken();
     else break;
-    if ((sym == _string) || (sym == _variable)) sym = __expression(sym);
-    else break;
+    sym = __expression(sym);
     if (sym == _rpar) sym = __gettoken();
     else break;
     _code.add(startsym);
@@ -958,8 +1057,7 @@ TCodesym TExpression::__factor(TCodesym startsym)
     sym = __gettoken();
     if (sym == _lpar) sym = __gettoken(TRUE);
     else break;
-    if ((sym == _string) || (sym == _variable)) sym = __expression(sym);
-    else break;
+    sym = __expression(sym);
     if (sym == _comma) sym = __gettoken(TRUE);
     else break;
     sym = __expression(sym);
@@ -1005,29 +1103,25 @@ TCodesym TExpression::__factor(TCodesym startsym)
 
 TCodesym TExpression::__term(TCodesym startsym)
 {
-  TCodesym      sym;
-
-  sym = __factor(startsym);
-  while ((sym != _endsym) && ((sym == _multiply) || (sym == _divide)))
+  TCodesym sym = __factor(startsym);
+  while (sym == _multiply || sym == _divide)
   {
-    TCodesym savedsym   = sym;
+    const TCodesym savedsym = sym;
     sym = __gettoken();
     sym = __factor(sym);
     _code.add(savedsym);
   }
-
   return sym;
 }
 
 
 TCodesym TExpression::__expression(TCodesym startsym)
-  
 {
   TCodesym      sym;
-
   if ((startsym == _minus) || (startsym == _not) || (startsym == _plus))
     sym =__gettoken();
-  else sym = startsym;
+  else 
+    sym = startsym;
   sym = __term(sym);
   if ((startsym == _minus) || (startsym == _not))
     _code.add(startsym == _not ? startsym  : _chgs);
@@ -1050,18 +1144,20 @@ bool TExpression::set(const char* expression, TTypeexp type)
   _original = expression; 
   _type = type; 
   _dirty = TRUE; 
-  return compile(expression, type); 
+  return compile(_original, type); 
 }
 
 bool TExpression::compile(const char* expression, TTypeexp type)
 
 {
-  TString       sc(256);
   TCodesym      currsym;
                          
   _user_func_defined = FALSE;                      
   _s = expression;
-  _type = type;
+  _type = type;  
+  
+/*  
+  TString       sc(256);
   while (((currsym = __gettoken()) != _endsym) && (currsym != _invalid))
   {
     if (currsym == _variable)
@@ -1102,14 +1198,17 @@ bool TExpression::compile(const char* expression, TTypeexp type)
       else sc << " " << _tok;
   }
   _s = sc;
+*/  
   _val = real(0.0);
   _code.clear();
-  if (!*_s) return TRUE;
-  if ((currsym = __gettoken()) == _invalid) return FALSE;
+  if (*_s == '\0') 
+    return TRUE;
+  if ((currsym = __gettoken()) == _invalid) 
+    return FALSE;
   return __expression(currsym) == _endsym;
 }
 
-const char* TExpression::last_compiled_token() const
+const char* TExpression::last_token() const
 {
   return _tok;
 }
diff --git a/include/expr.h b/include/expr.h
index d06905baf..5f2dbed49 100755
--- a/include/expr.h
+++ b/include/expr.h
@@ -1,14 +1,15 @@
 #ifndef __EXPR_H
 #define __EXPR_H
 
-#ifndef __STRINGS_H
-#include <strings.h>
-#endif
-
 #ifndef __REAL_H
 #include <real.h>
 #endif
 
+#ifndef __STACK_H
+#include <stack.h>
+#endif
+
+
 // @doc INTERNAL
 
 // @enum TCodesym | Lista di simboli/istruzioni possibili
@@ -363,7 +364,14 @@ public:
   {}
 };
                
-class TStack;
+class TEval_stack : public TStack
+{ 
+public:
+  real& pop_real(); 
+  real& peek_real(); 
+  TString& pop_string();
+  TString& peek_string();
+};
                
 // @doc EXTERNAL
 
@@ -396,7 +404,7 @@ class TExpression : public TObject
   // @access Protected Member
 protected:
   // @cmember funzione utente da ricalcolare
-  virtual bool user_func_dirty() { return _user_func_defined;}
+  virtual bool user_func_dirty() const { return _user_func_defined; }
   // @cmember stampa un messaggio d'errore
   virtual bool print_error(const char* msg) const;
   // @cmember Valuta (calcola) l'espressione
@@ -418,7 +426,7 @@ protected:
 protected: // TObject
   // @cmember Stampa l'espressione su <p out> (serve per implementare l'insertore)
   virtual void print_on(ostream& out) const ;
-  virtual void evaluate_user_func(int index, int nparms, TStack & stack, TTypeexp type) const;
+  virtual void evaluate_user_func(int index, int nparms, TEval_stack& stack, TTypeexp type) const;
   virtual int parse_user_func(const char * name, int nparms) const { return -1; }
 
   // @access Public Member
@@ -460,7 +468,7 @@ public:
   { _type = type; }
   // @cmember Setta l'espressione e la compila (ritorna il risultato della compilazione)
   bool set(const char* expression, TTypeexp type = _numexpr);
-  const char* last_compiled_token() const;
+  const char* last_token() const;
   // @cmember Ritorna l'espressione originale 
   const char * string() const { return _original; }
 
diff --git a/include/printapp.cpp b/include/printapp.cpp
index a146c5ab8..5a424e6c6 100755
--- a/include/printapp.cpp
+++ b/include/printapp.cpp
@@ -886,7 +886,7 @@ void TPrint_application::set_row (
         if (ch == 't' || ch == 'a')
           t << 's';
         else if (ch == 'r')
-#ifdef __LONGDOUBLE
+#ifdef __LONGDOUBLE__
           t << "Lf";
 #else        
           t << 't';
diff --git a/include/progind.cpp b/include/progind.cpp
index 3119b39e3..2399be421 100755
--- a/include/progind.cpp
+++ b/include/progind.cpp
@@ -28,14 +28,9 @@ TIndwin::TIndwin(long max, const char* txt, bool cancel,  bool bar, int div)
   word maxlen = div;
   const word lines = measure_text(testo, maxlen);
   
-  int ver = lines+3;
   int hor = maxlen+3; if (hor > 78) hor = 78;
-  
-  if (bar) 
-  {
-    _bar = ver * CHARY;
-    ver += 2;
-  }  
+  int ver = lines+3;
+  ver += bar ? 2 : 0;
   ver += cancel ? 2 : 0;
 
   set_win(create_interface(TASK_WIN, -1, -1, hor, ver, TITLE_TEXT, this, FALSE));
@@ -45,6 +40,12 @@ TIndwin::TIndwin(long max, const char* txt, bool cancel,  bool bar, int div)
   testo.replace('\n', '\r');
   _text->set_caption(testo);
   
+  if (bar)
+  {                    
+    RCT r; _text->get_rect(r);
+    _bar = r.bottom + CHARY;
+  }
+  
   if (cancel)
   {
     _cancel = new TPushbutton_control(win(), DLG_CANCEL, -11, -1, 10, 2, "", "Annulla", BMP_CANCEL);
diff --git a/include/rectypes.h b/include/rectypes.h
index 3a242c6cf..040fc8457 100755
--- a/include/rectypes.h
+++ b/include/rectypes.h
@@ -43,7 +43,7 @@ enum TDirop {
 
 // @enum TFieldtypes | Elenco tipi di campi
 enum TFieldtypes { 
-     _nullfld,     // @emem Campo vuoto
+     _nullfld,     // @emem Campo non definito
      _alfafld,     // @emem Campo di tipo alfanumerico
      _intfld,      // @emem Campo di tipo intero
      _longfld,     // @emem Campo di tipo intero lungo
diff --git a/include/relation.cpp b/include/relation.cpp
index 69f6f3632..112232848 100755
--- a/include/relation.cpp
+++ b/include/relation.cpp
@@ -1271,7 +1271,7 @@ TRecnotype TCursor::readrec()
 // @rdesc Ritorna il numero di errore che si verifica nel porre il lock (NOERR) se
 //    non si verificano errori
 int TCursor::lock(
-    TReclock l) // @parm Tipo di locke da porre sul record (vedi <t TReclock>)
+    TReclock l) // @parm Tipo di lock da porre sul record (vedi <t TReclock>)
 {
   int rt=NOERR; 
   switch(l)
@@ -1685,8 +1685,10 @@ TFieldref& TFieldref::operator =(
     _fileid = pos = 0;
   }  
   
-  int par = s.find('[', pos);
-  _name = s.sub(pos, par); _name.strip(" ");
+  int par = s.find('[', pos); // Cerca la fine del nome del campo
+  _name = s.sub(pos, par);    // Estrae il nome del campo
+  _name.strip(" ");           // Elimina eventuali spazi superflui
+  _name.upper();              // Converte in maiuscolo il nome del campo
   
   if (par > 0)
   {
diff --git a/include/sheet.cpp b/include/sheet.cpp
index 970670909..224279e30 100755
--- a/include/sheet.cpp
+++ b/include/sheet.cpp
@@ -1081,8 +1081,11 @@ bool TBrowse_sheet::browse_field_handler(TMask_field& f, KEY k)
       c.set(f.get());                          
     
     TBrowse* b = e.browse();
-    b->do_input(FALSE);
-    rec = b->cursor()->read(_isgteq);
+    if (b)
+    {
+      b->do_input(FALSE);
+      rec = b->cursor()->read(_isgteq);
+    }  
   } else
   if (k == K_F2)
     rec = 0; 
@@ -1125,7 +1128,8 @@ bool TBrowse_sheet::last_browse_field_handler(TMask_field& f, KEY k)
 TBrowse_sheet::TBrowse_sheet(TCursor* cursor, const char* fields,
                              const char* title, const char* head, byte buttons, 
                              TEdit_field* f, TToken_string& sibling)
-             : TCursor_sheet(cursor, fields, title, head, buttons, f->browse()->input_fields()), 
+             : TCursor_sheet(cursor, fields, title, head, buttons, 
+                             f->browse() ? f->browse()->input_fields() : 1), 
                _field(f), _sel(0)
 {
   TToken_string ca;         // Tag buttons
@@ -1143,11 +1147,15 @@ TBrowse_sheet::TBrowse_sheet(TCursor* cursor, const char* fields,
   if (n > 0)
     add_tag_button(0, ca, _sel);
   
+  TBrowse* browse = f->browse();
+  if (browse == NULL)
+    return;
+
   TToken_string tids = head;
   TToken_string tfns = fields;                                       
-  TToken_string ids  = f->browse()->get_input_fields();  
-  TToken_string fns  = f->browse()->get_input_field_names();  
-
+  TToken_string ids  = browse->get_input_fields();   
+  TToken_string fns  = browse->get_input_field_names();  
+  
   TEditable_field* e = NULL;
   short y  = 0;
   for (const char* i = ids.get(0); i; i = ids.get())
diff --git a/include/stack.cpp b/include/stack.cpp
index 7836228ba..9f7f16c80 100755
--- a/include/stack.cpp
+++ b/include/stack.cpp
@@ -15,12 +15,12 @@ void TStack::push(TObject* o)
 
 TObject& TStack::pop()
 {
-  CHECK(count() > 0, "Stack underflow!");
+  CHECK(_sp > 0, "Stack underflow!");
   return (*this)[--_sp];
 }
 
 TObject& TStack::peek(int depth) const
 {
-  CHECK(depth > _sp, "Stack underflow!");
+  CHECKD(depth >= 0 && depth < _sp, "Stack depth error: ", depth);
   return (*this)[_sp-depth-1];
 }
diff --git a/include/strings.cpp b/include/strings.cpp
index e6dbd942c..d8d27e1c0 100755
--- a/include/strings.cpp
+++ b/include/strings.cpp
@@ -402,7 +402,7 @@ const TString& TString::mid(
 #ifdef DBG
   if (from < 0)
   {
-    yesnofatal_box("Ivalid MID parameter: from = %d", from);
+    NFCHECK("Ivalid MID parameter: from = %d", from);
     from = 0;
   }
 #endif
@@ -435,11 +435,9 @@ TString& TString::cut(int n)
   CHECKD(n >= 0, "Invalid TString::cut position ", n);
   if (n <= _size)
     _str[n] = '\0';
-#ifdef DBG
   else
-    yesnofatal_box("Hai tagliato a %d la stringa '%s' lunga %d(%d)",
-                   n, _str, len(), size());
-#endif    
+    NFCHECK("Hai tagliato a %d la stringa '%s' lunga %d(%d)",
+            n, _str, len(), size());
   return *this;
 }
 
diff --git a/include/text.h b/include/text.h
index bbce14092..6408b10fc 100755
--- a/include/text.h
+++ b/include/text.h
@@ -198,7 +198,7 @@ public:
   
   // @cmember Costruttore
   TTextfile(const char* file = NULL, int pagesize = DEFAULT_PAGESIZE, direction preferred = updown, bool interactive = TRUE);
-  // @cmember DIstruttore
+  // @cmember Distruttore
   virtual ~TTextfile();
 };
 
diff --git a/include/viswin.cpp b/include/viswin.cpp
index de393102e..44a68a0c3 100755
--- a/include/viswin.cpp
+++ b/include/viswin.cpp
@@ -667,8 +667,8 @@ void TViswin::paint_screen ()
       xvt_dwin_draw_set_pos (win (), b);
       xvt_dwin_draw_line (win (), e);
       set_brush (COLOR_DKGRAY);
-      bar (X_OFFSET-1, (int)(j+(long)Y_OFFSET-origin().y),(int)columns(),
-           (int)(rows()-(long)BUTTONROW_SIZE));
+      bar (X_OFFSET-1, (int)(j+(long)Y_OFFSET-origin().y),
+           (int)columns()+1, (int)(rows()-(long)BUTTONROW_SIZE));
       autoscroll (TRUE);
       break;
 #endif
@@ -2524,7 +2524,10 @@ TViswin::TViswin(const char *fname,
     // load info from config on buttons and rulers
     TConfig cnf(CONFIG_USER, "Visualizzazione");
     _showbuts = cnf.get_bool("Bottoni",  NULL, -1,TRUE);
-    _rulers   = cnf.get_bool("Righelli", NULL, -1,TRUE);  
+    
+    // Se rulers vale 3 allora leggi dal config il vero valore
+    if (_rulers != FALSE && _rulers != TRUE)
+      _rulers = cnf.get_bool("Righelli", NULL, -1,TRUE);  
   }
   
   const int larg = 76;
diff --git a/include/viswin.h b/include/viswin.h
index 562858f3c..a77f89345 100755
--- a/include/viswin.h
+++ b/include/viswin.h
@@ -328,11 +328,11 @@ public:
   void find_next();
 
   // @cmember void | TViswin | const char* fname=NULL, const char* title=NULL, 
-  //                           bool editbutton=TRUE, int width=0, bool rulers=TRUE,
+  //                           bool editbutton=TRUE, int width=0, bool rulers=3,
   //                   WINDOW parent=NULL_WIN, TBrowsefile_field*=NULL | Costruttore
   TViswin(const char* fname=NULL, const char* title=NULL, bool editbutton=TRUE,
           bool printbutton=TRUE, bool linkbutton=TRUE, int x=-1, int y=-1, int height=0,
-          int width=0, bool rulers=TRUE, WINDOW parent=NULL_WIN, TBrowsefile_field* =NULL);
+          int width=0, bool rulers=3, WINDOW parent=NULL_WIN, TBrowsefile_field* =NULL);
   // @cmember Distruttore
   virtual ~TViswin ();
 };