std::uses_allocator<std::dynarray>
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                    |   template< class T, class Alloc > 
struct uses_allocator<dynarray<T>, Alloc> : std::true_type;  | 
(since C++14) | |
Provides a specialization of the std::uses_allocator type trait for std::dynarray. A dynarray may be constructed with an allocator, even though the class does not have allocator_type member type. 
[edit] See also
|    (C++11) 
 | 
   checks if the specified type supports uses-allocator construction   (class template)  |