program Project2;

{$APPTYPE CONSOLE}

{$R *.res}

uses
  System.SysUtils, Classes;

type
  TMyClass = class of TMyObject;
  TMyObject = class (TPersistent)
    constructor Create; virtual;
    function AsStr: string; virtual;
  end;

  TMyObject1 = class (TMyObject)
    constructor Create; override;
    procedure Assign(Source: TPersistent); override;
    function AsStr: string; override;
  end;

  TMyObject2 = class (TMyObject)
    constructor Create; override;
    procedure Assign(Source: TPersistent); override;
    function AsStr: string; override;
  end;

constructor TMyObject.Create;
begin
end;

function TMyObject.AsStr: string;
begin
  Result := 'TMyObject';
end;

constructor TMyObject1.Create;
begin
  inherited Create;
end;

procedure TMyObject1.Assign(Source: TPersistent);
begin
  if Source is TMyObject1 then ;
end;

function TMyObject1.AsStr: string;
begin
  Result := 'TMyObject1';
end;

constructor TMyObject2.Create;
begin
  inherited Create;
end;

procedure TMyObject2.Assign(Source: TPersistent);
begin
  if Source is TMyObject2 then ;
end;

function TMyObject2.AsStr: string;
begin
  Result := 'TMyObject2';
end;

var
  M: TMyObject1;
  Clone: TMyObject;
begin
  try
    M := TMyObject1.Create;

    Clone := TMyClass(M.ClassType).Create;
    Clone.Assign(M);

    WriteLn(M.AsStr);
    WriteLn(Clone.AsStr);
    ReadLn;

    Clone.Free;
    M.Free;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
end.