std::allocator<T>::construct
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                    |   Defined in header  <memory>
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|   void construct( pointer p, const_reference val );  | 
(1) | (until C++11) | 
|   template< class U, class... Args > void construct( U* p, Args&&... args );  | 
(2) |  (since C++11)  (deprecated in C++17) (removed in C++20)  | 
Constructs an object of type T in allocated uninitialized storage pointed to by p, using placement-new
1) Calls new((void *)p) T(val)
2) Calls ::new((void *)p) U(std::forward<Args>(args)...)
Parameters
| p | - | pointer to allocated uninitialized storage | 
| val | - | the value to use as the copy constructor argument | 
| args... | - | the constructor arguments to use | 
Return value
(none)
See also
|    [static]  | 
   constructs an object in the allocated storage  (function template)  | 
|    allocation functions   (function)  |