unit Unit1;

interface

uses
  Vcl.Forms, Vcl.Dialogs, System.Rtti, System.Classes, Vcl.Controls,
  Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  end;

  TSession = class sealed(TObject)
  public
    function Load<TRecord: class, constructor>(const AId: TValue): TRecord;
  end;

  UUId = ShortString;
  RawString = string;

  TPerson = class(TObject)
  private
    FName: RawString;
    FId: UUId;
  public
    property Id: UUId read FId write FId;
    property Name: RawString read FName write FName;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

{ TSession }

function TSession.Load<TRecord>(const AId: TValue): TRecord;
{ Mock }
var
  VPerson: TPerson;
begin
  { Mock }
  VPerson := TPerson.Create;
  VPerson.Id := 'B62DDA747C4E490A89B53EDE2B973138';
  VPerson.Name := 'Test OK';

  Result := TRecord(VPerson);
end;

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
var
  VPerson: TPerson;
  VSession: TSession;
begin
  VSession := TSession.Create;
  VPerson := nil;
  try
    VPerson := VSession.Load<TPerson>('B62DDA747C4E490A89B53EDE2B973138');
    ShowMessageFmt('ID: %s, Name: %s', [VPerson.Id, VPerson.Name]);
  finally
    VPerson.Free;
    VSession.Free;
  end;
end;

end.