Specifies that an object of the type can be constructed into uninitialized storage from an rvalue of that type by a given allocator.
The type T
is MoveInsertable into the container X
whose value_type
is identical to T
if, given.
A | an allocator type |
m | an lvalue of type A |
p | the pointer of type T* prepared by the container |
rv | rvalue expression of type T |
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, rv);
And after evaluation, the value of *p
is equivalent to the value formerly held by rv
(rv
remains valid, but is in an unspecified state.).
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.
If A
is std::allocator<T>
, then this will call placement-new, as by ::new((void*)p) T(rv)
. This effectively requires T
to be move constructible.
If std::allocator<T>
or a similar allocator is used, a class does not have to implement a move constructor to satisfy this type requirement: a copy constructor that takes a const T&
argument can bind rvalue expressions. If a MoveInsertable class implements a move constructor, it may also implement move semantics to take advantage of the fact that the value of rv
after construction is unspecified.
CopyInsertable |
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