anchor.diff:  procedure TmXmlElement.SetFloatAttribute(const aName: TmXmlString; const aValue: TNullableDouble);
   begin
     if aValue.NotNull then
  -    Self.SetFloatAttribute(aName, aValue.Value);
  +    Self.SetFloatAttribute(aName, aValue.Value)
  +  else
  +    Self.DeleteAttribute(aName);
   end;
   
   function TmXmlElement.GetFloatAttribute(const aName: TmXmlString): Double;
  
positive.code: procedure TmXmlElement.SetDateAttribute(const aName: TmXmlString; const aValue: TNullableDateTime);
  begin
    if aValue.NotNull then
      Self.SetDateAttribute(aName, aValue.Value);
  end;
  
  function TmXmlElement.GetDateAttribute(const aName: TmXmlString): TDateTime;
  
negative.code: procedure TmXmlElement.SetIntegerAttribute(const aName: TmXmlString; const aValue: TNullableInteger);
  begin
    if aValue.NotNull  then
      Self.SetIntegerAttribute(aName, aValue.Value)
    else
      Self.DeleteAttribute(aName);
  end;
  
  { TmXmlDocument }
  