std::std::uses_allocator<std::packaged_task>
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                    < cpp | thread | packaged task
                    
                                                            
                    |   template< class R, class Alloc > struct uses_allocator<std::packaged_task<R>, Alloc> : true_type { };  | 
(since C++11) | |
Provides a specialization of the std::uses_allocator type trait for std::packaged_task.
[edit] See also
|    (C++11)  | 
   checks if the specified type supports uses-allocator construction   (class template)  |