Difference between revisions of "cpp/thread/promise/set exception"
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Andreas Krug (Talk | contribs) m (fmt, {{c}}, headers sorted) |
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| − | {{cpp/thread/promise/title | set_exception}} | + | {{cpp/thread/promise/title|set_exception}} |
{{cpp/thread/promise/navbar}} | {{cpp/thread/promise/navbar}} | ||
| − | {{ddcl | since=c++11 | | + | {{ddcl|since=c++11| |
void set_exception( std::exception_ptr p ); | void set_exception( std::exception_ptr p ); | ||
}} | }} | ||
| − | Atomically stores the exception pointer {{ | + | Atomically stores the exception pointer {{|p}} into the shared state and makes the state ready. |
The operation behaves as though {{lc|set_value}}, {{tt|set_exception}}, {{lc|set_value_at_thread_exit}}, and {{lc|set_exception_at_thread_exit}} acquire a single mutex associated with the promise object while updating the promise object. | The operation behaves as though {{lc|set_value}}, {{tt|set_exception}}, {{lc|set_value_at_thread_exit}}, and {{lc|set_exception_at_thread_exit}} acquire a single mutex associated with the promise object while updating the promise object. | ||
| Line 15: | Line 15: | ||
===Parameters=== | ===Parameters=== | ||
{{par begin}} | {{par begin}} | ||
| − | {{par | p | exception pointer to store. The behavior is undefined if {{ | + | {{par|p|exception pointer to store. The behavior is undefined if {{|p}} is null}} |
{{par end}} | {{par end}} | ||
| Line 30: | Line 30: | ||
===Example=== | ===Example=== | ||
{{example | {{example | ||
| − | + | |code= | |
| − | + | ||
| − | + | ||
#include <future> | #include <future> | ||
| + | |||
| + | |||
int main() | int main() | ||
| Line 40: | Line 40: | ||
std::future<int> f = p.get_future(); | std::future<int> f = p.get_future(); | ||
| − | std::thread t([&p]{ | + | std::thread t([&p] |
| − | try { | + | { |
| + | try | ||
| + | { | ||
// code that may throw | // code that may throw | ||
throw std::runtime_error("Example"); | throw std::runtime_error("Example"); | ||
| − | } catch(...) { | + | } |
| − | try { | + | catch (...) |
| + | { | ||
| + | try | ||
| + | { | ||
// store anything thrown in the promise | // store anything thrown in the promise | ||
p.set_exception(std::current_exception()); | p.set_exception(std::current_exception()); | ||
// or throw a custom exception instead | // or throw a custom exception instead | ||
// p.set_exception(std::make_exception_ptr(MyException("mine"))); | // p.set_exception(std::make_exception_ptr(MyException("mine"))); | ||
| − | } catch(...) {} // set_exception() may throw too | + | } |
| + | catch (...) {} // set_exception() may throw too | ||
} | } | ||
}); | }); | ||
| − | try { | + | try |
| + | { | ||
std::cout << f.get(); | std::cout << f.get(); | ||
| − | } catch(const std::exception& e) { | + | } |
| + | catch (const std::exception& e) | ||
| + | { | ||
std::cout << "Exception from the thread: " << e.what() << '\n'; | std::cout << "Exception from the thread: " << e.what() << '\n'; | ||
} | } | ||
t.join(); | t.join(); | ||
} | } | ||
| − | + | |output= | |
Exception from the thread: Example | Exception from the thread: Example | ||
}} | }} | ||
| Line 67: | Line 76: | ||
===See also=== | ===See also=== | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc inc | cpp/thread/promise/dsc set_exception_at_thread_exit}} | + | {{dsc inc|cpp/thread/promise/dsc set_exception_at_thread_exit}} |
{{dsc end}} | {{dsc end}} | ||
{{langlinks|de|es|fr|it|ja|pt|ru|zh}} | {{langlinks|de|es|fr|it|ja|pt|ru|zh}} | ||