anchor.diff:      if Result then
         Self.Value:= tmpDouble;
     end;
  +  Self.FTagChanged:= Result;
   end;
   
   function TNullableDouble.AsString: String;
  
positive.code:     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;
  
  
negative.code:     Self.IsNull:= true
    else
      Self.Value:= aValue;
    FTagChanged:= false;
  end;
  
  procedure TNullableBoolean.Assign(const aValue: string);
  