Talk:cpp/thread/future/get

vc2012\\vc11\\crt\\future.cpp

there is an error with the

static const char *const _Future_messages[] = { // messages for future errors "broken promise", "future already retrieved", "promise already satisfied", "no state" };

this code generated an invalid acceso to "_Future_messages" because _Mycode.value() return 4.

const char *__CLR_OR_THIS_CALL what() const _THROW0() { // get message string return (_Get_future_error_what(_Mycode.value())); }

// code example

   std::future<int> empty;
   try {
       int n = empty.get();
   } catch (const std::future_error& e) {
      const error_code eCode = e.code();
      char *sValue = (char*)e.what();
      std::cout << "Caught a future_error with code " << eCode.message()
                 << " - what" << sValue << endl;
   }

works for me, and for the online compilers (even http://ideone.com/bkXoAM ). Perhaps you need to direct this query to Microsoft Connect? --Cubbi (talk) 03:37, 16 October 2013 (PDT)

The statement 'Any shared state is released' appears to be wrong. The standards says that shared state is released in std::future's destructor (or on reassignment).

In particular, the reference specialisation is returning a reference to the value in the shared state.

The standard says that future::get "releases any shared state", in futures.unique_future/15.2. --Cubbi (talk) 07:30, 31 March 2017 (PDT)

Our wording is broken here: future<T&>::get() returns "the reference stored as value in the object's shared state", not a reference to some value in the shared state (what value would that even be?). Fixed. T. Canens (talk) 10:51, 31 March 2017 (PDT)