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Using Object instead of Class generates compiler error

Hi everyone.

To prevent me from having all the methods of the TObject class while having almost all the advantages of a class, I started to use the Object keyword (to replace Class). Everything worked fine until I started to use them with indexed properties. Doing so forced me to do something like : Result (Object) := MyObject. The problem is that it generates a compiler error with delphi 5 (ex.: error #12345 You should not receive this message...contact Borland...blablabla).

The help files says that Object is supported only for backward compatibility.

Any clue on why it was leaved, what replaced it and how I can make this work?

GunDamn

Igor UL7AAjr

Hi comptebidon81,

here is small sample. It shows how to create new object, put it into list and then get some it's property by index from the list.

-----
Igor

type
// your object declaration
PMyObject = ^TMyObject;
TMyObject = object
private
FX: Integer;
FY: Integer;

procedure SetX(Value: Integer);
procedure SetY(Value: Integer);
public
property X: Integer read FX write SetX;
property Y: Integer read FY write SetY;
end;

// list that keep your objects
TMyList = class(TList)
private
function GetMyObject(I: Integer): TMyObject;
public
property MyObjects[Index: Integer]: TMyObject read GetMyObject;
end;

implementation

procedure TMyObject.SetX(Value: Integer);
begin
FX := Value;
end;

procedure TMyObject.SetY(Value: Integer);
begin
FY := Value;
end;

function TMyList.GetMyObject(I: Integer): TMyObject;
begin
Result := PMyObject(Items[I])^;
end;

.....

var
L: TMyList;
M: PMyObject;
begin
L := TMyList.Create;

New(M);
M.X := 128;
M.Y := 111;
L.Add(M);

New(M);
M.X := 500;
M.Y := 555;
L.Add(M);

Caption := IntToStr(L.MyObjects[0].X);

end;

comptebidon81

ASKER

Thats not bad, but its not what I want.

I already build my Class. It works perfectly except for all the methods that I don't want to see. But I think it is better than having to work with a List. This class will be used by other and I have to make it simple. With my method, the user will have only one object to declare and create.

I don't know if it is possible to do better, but I'd like to try. I would also like to know what happened with "object"

Thanks anyway, Igor
GunDamn

Igor UL7AAjr

Hi comptebidon81,

now I'm living the office, but you can send me the part of your code that doesn't work. I will take a look tomorrow.

-----
Igor.

comptebidon81

ASKER

My code works fine. Its the compiler that has a bug. It stops at the end of a procedure because with the message [Fatal Error] BindingData.pas(1089): Internal error: C10652
This is the line that generates it:
Result := rMyObject;
were Result and rMyObject are declared with the keyword object (similar to class(Tobject) but with no properties or method)

That is why I wanted to know what happened with this "object" thing.

Thanks again
GunDamn

ASKER CERTIFIED SOLUTION

Igor UL7AAjr

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comptebidon81

ASKER

It took about a year, but I finnally closed this question!