bool valid() const; | (since C++11) |
Checks if the future refers to a shared state.
This is the case only for futures that were not default-constructed or moved from. Unlike std::future
, std::shared_future
's shared state is not invalidated when get()
is called.
The behavior is undefined if any member function other than the destructor, the copy-assignment operator, the move-assignment operator, or valid
is called on a shared_future
that does not refer to shared state (although implementations are encouraged to throw std::future_error
indicating no_state
in this case). It is valid to move or copy from a shared_future object for which valid()
is false
.
(none).
true
if *this refers to a shared state, otherwise false
.
noexcept
specification: noexcept
waits for the result to become available (public member function) |
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