anchor.diff:  
   { TNullableUnicodeString }
   
  -
  +(*
   function TNullableUnicodeString.GetValue: UnicodeString;
   begin
     if (FIsNull) then
  
positive.code: 
        property Value : AnsiString read GetValue write SetValue;
    end;
  
  
    { TNullableDateTime }
  
  
negative.code: 
      procedure Assign(aSource : TNullableInteger); overload;
      procedure Assign(aSourceField : TField); override; overload;
      procedure Assign(const aValue : String); override; overload;
      procedure Assign(const aValue : Variant); override; overload;
  
      function CheckIfDifferentAndAssign(const aValue : Variant) : boolean;
      function AsVariant : Variant; override;
      function AsString : String;
  
      class function StringToVariant(const aValue : String) : Variant;
  
      property Value : Integer read GetValue write SetValue;
    end;
  