std::promise::set_value

 

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std::promise

Member functions

promise::promise

promise::~promise

promise::operator=

promise::swap

Getting the result

promise::get_future

Setting the result

promise::set_value

promise::set_value_at_thread_exit

promise::set_exception

promise::set_exception_at_thread_exit

 

void set_value( const R& value );	(1)	(member only of generic promise template) (since C++11)
void set_value( R&& value );	(2)	(member only of generic promise template) (since C++11)
void set_value( R& value );	(3)	(member only of promise<R&> template specialization) (since C++11)
void set_value()	(4)	(member only of promise<void> template specialization) (since C++11)

Stores the value into the shared state and makes the state ready.

The operation is atomic, i.e. it behaves as though they acquire a single mutex associated with the promise object while updating the promise object.

An exception is thrown if there is no shared state or the shared state already stores a value or exception.

Parameters

value

-

value to store in the shared state

Return value

(none)

Exceptions

std::future_error on the following conditions:

• *this has no shared state. The error category is set to no_state.

• The shared state already stores a value or exception. The error category is set to promise_already_satisfied.

Additionally:

1-2) Any exception thrown by the copy constructor of value

3) Any exception thrown by the move constructor of value

See also

set_exception	sets the result to indicate an exception (public member function)