Using TTask::Future<> in Embarcadero XE7 C++ - c++

Question

I tried to make "Tutorial: Using Futures from the Parallel Programming Library" from here.
I created project "File > New > Multi-Device Application - C++Builder > Blank Application" and copy source from link.
#include <System.Threading.hpp>
.h
public: // User declarations
System::DelphiInterface<IFuture__1<System::String> > FutureString;
System::String __fastcall FutureHandler(TObject* Sender);
.cpp
void __fastcall TForm1::Button1Click(TObject *Sender) {
FutureString = TTask::Future<System::String>(0, this->FutureHandler);
}
System::String __fastcall TForm1::FutureHandler(TObject* Sender) {
Sleep(3000);
System::String str = System::String().sprintf(L"Hello %d", Random(42));
return str;
}
After build I'm getting this error message:
[ilink64 Error] Error: Unresolved external 'System::DelphiInterface > System::Threading::TTask::Future(System::TObject*, System::UnicodeString (* __closure)(System::TObject*))' referenced from C:\USERS\PC\DESKTOP\64BIT\WIN64\DEBUG\UNIT1.O
declaration from System.Threading.hpp
template<typename T> static System::DelphiInterface<IFuture__1<T> >
__fastcall Future(System::TObject* Sender, T __fastcall (__closure *)
(System::TObject* Sender) )/* overload */;
===
protected:
HIDESBASE System::DelphiInterface<IFuture__1<T> > __fastcall Start(void);
T __fastcall GetValue(void);
#ifndef _WIN64
typedef T __fastcall (__closure *_dt_System_Threading_2)(System::TObject* Sender);
__fastcall TFuture__1(System::TObject* Sender, _dt_System_Threading_2 Event,
const System::DelphiInterface<System::Sysutils::TFunc__1<T> > Func, TThreadPool* APool)/* overload */;
#else /* _WIN64 */
__fastcall TFuture__1(System::TObject* Sender, TFunctionEvent__1<T> Event, const System::DelphiInterface<System::Sysutils::TFunc__1<T> > Func, TThreadPool*
APool)/* overload */;
#endif /* _WIN64 */
private:
// __classmethod void __fastcall Destroy#();
protected:
/* TTask.Create */ inline __fastcall TFuture__1(System::TObject* Sender,
System::Classes::TNotifyEvent Event, const System::Sysutils::_di_TProc AProc, TThreadPool* const APool, TTask* const AParent, TTask::TCreateFlags CreateFlags)/* overload */ : TTask(Sender, Event, AProc, APool, AParent, CreateFlags) { }
public:
/* TTask.Create */ inline __fastcall TFuture__1(void)/* overload */ :
TTask() { }
/* TTask.Destroy */ inline __fastcall virtual ~TFuture__1(void) { }
private:
void *__IFuture__1; // IFuture__1<T>
public:
operator IFuture__1<T>*(void) { return (IFuture__1<T>*)&__IFuture__1; }
};
how to cope with this error?