diff --git a/uppsrc/Core/Defs.h b/uppsrc/Core/Defs.h
index 37f9d8581..1f3108d25 100644
--- a/uppsrc/Core/Defs.h
+++ b/uppsrc/Core/Defs.h
@@ -467,7 +467,7 @@ extern const Nuller Null;
 
 template <class T> void SetNull(T& x) { x = Null; }
 
-template <class T> bool IsNull(const T& x) { return x.IsNullInstance(); }
+template <class T> bool IsNull(const T& x)       { return x.IsNullInstance(); }
 
 template<> inline bool  IsNull(const int& i)     { return i == INT_NULL; }
 template<> inline bool  IsNull(const int64& i)   { return i == INT64_NULL; }
diff --git a/uppsrc/ide/Debuggers/Data.cpp b/uppsrc/ide/Debuggers/Data.cpp
index 8fa4c25bb..93d899dda 100644
--- a/uppsrc/ide/Debuggers/Data.cpp
+++ b/uppsrc/ide/Debuggers/Data.cpp
@@ -118,6 +118,7 @@ void Pdb::Autos()
 {
 	VectorMap<String, Value> prev = DataMap(autos);
 	autos.Clear();
+	autotext.Replace("//", "");
 	CParser p(autotext);
 	TryAuto("this", prev);
 	while(!p.IsEof())
@@ -295,6 +296,7 @@ bool Pdb::Tip(const String& exp, CodeEditor::MouseTip& mt)
 
 void Pdb::Data()
 {
+DLOG("Data");
 	switch(tab.Get()) {
 	case TAB_AUTOS: Autos(); break;
 	case TAB_LOCALS: Locals(); break;
diff --git a/uppsrc/ide/Debuggers/Pdb.cpp b/uppsrc/ide/Debuggers/Pdb.cpp
index 18f37daa9..6b7863a1e 100644
--- a/uppsrc/ide/Debuggers/Pdb.cpp
+++ b/uppsrc/ide/Debuggers/Pdb.cpp
@@ -233,6 +233,8 @@ Pdb::Pdb()
 	autos.WhenBar = THISBACK(AutosMenu);
 	autos.WhenLeftDouble = THISBACK1(ExploreKey, &autos);
 
+DLOG("TEST");
+
 	int c = EditField::GetStdHeight();
 	explorer.AddColumn("", 1);
 	explorer.AddColumn("", 6).SetDisplay(Single<VisualDisplay>());
diff --git a/uppsrc/ide/Debuggers/Pdb.h b/uppsrc/ide/Debuggers/Pdb.h
index 0567ba05d..501f9d464 100644
--- a/uppsrc/ide/Debuggers/Pdb.h
+++ b/uppsrc/ide/Debuggers/Pdb.h
@@ -327,6 +327,7 @@ struct Pdb : Debugger, ParentCtrl {
 	Val        Comparison(CParser& p);
 	Val        Exp0(CParser& p);
 	Val        Exp(CParser& p);
+	void       CatInt(Visual& result, int64 val);
 	void       Visualise(Visual& result, Pdb::Val val, int expandptr, int slen);
 	void       Visualise(Visual& result, Pdb::Val val, int expandptr);
 	Visual     Visualise(Val v);
diff --git a/uppsrc/ide/Debuggers/Visualise.cpp b/uppsrc/ide/Debuggers/Visualise.cpp
index 4aa00b16a..8769b716d 100644
--- a/uppsrc/ide/Debuggers/Visualise.cpp
+++ b/uppsrc/ide/Debuggers/Visualise.cpp
@@ -48,6 +48,11 @@ bool IsOk(const String& q)
 	return true;
 }
 
+void Pdb::CatInt(Visual& result, int64 val)
+{
+	result.Cat(IntFormat(val), Red);
+}
+
 void Pdb::Visualise(Visual& result, Pdb::Val val, int expandptr, int slen)
 {
 	const int maxlen = 300;
@@ -79,7 +84,8 @@ void Pdb::Visualise(Visual& result, Pdb::Val val, int expandptr, int slen)
 		return;
 	}
 	if(val.type < 0) {
-		#define RESULTINT(x, type) case x: result.Cat(IntFormat((type)val.ival), Red); break;
+		#define RESULTINT(x, type) case x: CatInt(result, (type)val.ival); break;
+		#define RESULTINTN(x, type, t2) case x:  if(IsNull((t2)val.ival)) result.Cat("Null ", Magenta); CatInt(result, (type)val.ival); break;
 		switch(val.type) {
 		RESULTINT(BOOL1, bool)
 		RESULTINT(UINT1, byte)
@@ -87,12 +93,16 @@ void Pdb::Visualise(Visual& result, Pdb::Val val, int expandptr, int slen)
 		RESULTINT(UINT2, uint16)
 		RESULTINT(SINT2, int16)
 		RESULTINT(UINT4, uint32)
-		RESULTINT(SINT4, int32)
 		RESULTINT(UINT8, uint64)
-		RESULTINT(SINT8, int64)
+		RESULTINTN(SINT4, int32, int)
+		RESULTINTN(SINT8, int64, int64)
 		case DBL:
 		case FLT:
-			result.Cat(FormatDouble(val.fval, 20), Red); break;
+			if(IsNull(val.fval))
+				result.Cat("Null", Magenta);
+			else
+				result.Cat(FormatDouble(val.fval, 20), Red);
+			break;
 		case PFUNC: {
 			result.Cat(Hex(val.address), Red);
 			FnInfo fi = GetFnInfo(val.address);