std::packaged_task<R(Args...)>::valid

 

C++

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Concepts library (C++20)

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Technical Specifications

 

Thread support library

Threads
thread (C++11)
hardware_destructive_interference_sizehardware_constructive_interference_size (C++17)(C++17)
this_thread namespace
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Condition variables
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promise (C++11) future (C++11) shared_future (C++11) packaged_task (C++11) async (C++11)	launch (C++11) future_status (C++11) future_error (C++11) future_category (C++11) future_errc (C++11)

 

std::packaged_task

Member functions

packaged_task::packaged_task

packaged_task::~packaged_task

packaged_task::operator=

packaged_task::valid

packaged_task::swap

Getting the result

packaged_task::get_future

Execution

packaged_task::operator()

packaged_task::make_ready_at_thread_exit

packaged_task::reset

 

bool valid() const noexcept;		(since C++11)

Checks whether *this has a shared state.

Parameters

(none)

Return value

true if *this has a shared state, false otherwise.