Многопоточность и TTask

// Отделите правило языка от удачного запуска ThreadLifecycle.
program ThreadLifecycle;
uses System.Classes;
type
  TWorker = class(TThread)
  protected
    procedure Execute; override;
  end;
procedure TWorker.Execute;
begin
  while not Terminated do
    Sleep(10);
end;
var W: TWorker;
begin
  W := TWorker.Create(False);
  W.FreeOnTerminate := False;
  W.Terminate;
  W.WaitFor;
  W.Free;
end.

// Отделите правило языка от удачного запуска GracefulShutdown.
program GracefulShutdown;
uses System.Generics.Collections, System.Threading;
var Tasks: TList<ITask>;
procedure StopAll;
var T: ITask;
begin
  for T in Tasks do T.Cancel;
  for T in Tasks do T.Wait;
  Tasks.Clear;
end;
begin
  Tasks := TList<ITask>.Create;
  try
    StopAll;
  finally
    Tasks.Free;
  end;
end.

// Разберите TaskLogging.
program TaskLogging;
{$APPTYPE CONSOLE}
uses System.Classes, System.Threading, System.SysUtils;
function StartImport(const JobId: string): ITask;
begin
  Result := TTask.Run(
    procedure
    begin
      if JobId = '' then
        raise EArgumentException.Create('JobId is empty');
      Writeln(JobId, ' stage=validate thread=', TThread.Current.ThreadID);
      Writeln(JobId, ' stage=store thread=', TThread.Current.ThreadID);
    end);
end;
var
  Task: ITask;
begin
  Task := StartImport('job-17');
  Task.Wait;
end.

// Отделите правило языка от удачного запуска CooperativeCancel.
program CooperativeCancel;
uses System.Threading;
procedure RunWork(const Task: ITask);
var I: Integer;
begin
  for I := 1 to 1000000 do
  begin
    Task.CheckCanceled;
    { process one small portion }
  end;
end;
begin end.

// Проследите фактическое поведение QueueUi.
program QueueUi;
uses System.Classes, System.SysUtils, System.Threading, Vcl.StdCtrls;
procedure Calculate(Label1: TLabel);
begin
  TTask.Run(procedure
    var N: Integer;
    begin
      N := 40 + 2;
      TThread.Queue(nil, procedure begin Label1.Caption := N.ToString; end);
    end);
end;
begin end.

// Определите реальную гарантию в TaskException.
program TaskException;
uses System.Threading, System.SysUtils;
var Task: ITask;
begin
  Task := TTask.Run(procedure
    begin
      raise EInvalidOperation.Create('worker failed');
    end);
  Task.Wait;
  Writeln('done');
end.