Hi All!

Is there any way to pass a method function as the Compare parameter to a TList or is there a work around for it?

There are generics involved so it won't let me access the static symbol table.

As in:

type
   TMyClass = object
      fIndex : Integer;
      List : array of TList;
      function Compare( Item1, Item2 : Pointer) : Longint; // needs
access to fIndex
      procedure Sort;
   end;
implementation
function TMyClass.Compare( Item1, Item2 : Pointer ) : Longint;
begin
    case fIndex of
       0:  Result := some compare of Item1, Item2;// These compares are
implemented in an object from another unit
       1:  Result := another compare of Item1, Item2
    end;
end;
procedure TMyClass.Sort;
begin
   fIndex := 0;
   List[fIndex].Sort( @Compare );  // Compilation error, doesn't like
Compare being "of object"
end;

Thanks,

Don Ziesig

// Drop the TMyClass.
function Compare( Item1, Item2 : Pointer ) : Longint;
begin
   case fIndex of
      0:  Result := some compare of Item1, Item2;// These compares are
implemented in an object from another unit
      1:  Result := another compare of Item1, Item2
   end;
end;

Sort takes a function, not a method. There is a difference. A function pointer is, well one pointer. A method pointer (function/procedure of object) is tow pointers 1st pointer) for the function 2nd pointer) for the object instance
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It's a dreadful hack, but you could try something like:

type
   TClassListSortCompare = function (Item1, Item2: Pointer): Integer of
object;
procedure TMyClass.Sort;
var
   objectFunction: TClassListSortCompare;
   regularFunction: TListSortCompare;
begin
   fIndex := 0;
   ;
   regularFunction:=TListSortCompare(TMethod(objectFunction).Code);
   List[fIndex].Sort( regularFunction );
end;

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