C++ concepts: EmplaceConstructible (since C++11)
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                    Specifies that an object of the type can be constructed from a given set of arguments in uninitialized storage by a given allocator.
[edit] Requirements
The type T is EmplaceConstructible into the Container X (whose value_type is identical to T) from the arguments args if, given
  A
 | 
an allocator type | 
  m
 | 
  an lvalue of type A
 | 
  p
 | 
  the pointer of type T* prepared by the container
 | 
  args
 | 
zero or more arguments | 
where X::allocator_type is identical to std::allocator_traits<A>::rebind_alloc<T>,
the following expression is well-formed:
std::allocator_traits<A>::construct(m, p, args);
If X is not allocator-aware, the term is defined as if A were std::allocator<T>, except that no allocator object needs to be created, and user-defined specializations of std::allocator are not instantiated.
[edit] See Also
  CopyInsertable
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|
  MoveInsertable
 |