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std::deque<T,Allocator>::emplace_front

template< class... Args >
void emplace_front( Args&&... args );
(since C++11)
(until C++17)
template< class... Args >
reference emplace_front( Args&&... args );
(since C++17)

Inserts a new element to the beginning of the container. The element is constructed through std::allocator_traits::construct, which typically uses placement-new to construct the element in-place at the location provided by the container. The arguments args... are forwarded to the constructor as std::forward<Args>(args)....

All iterators, including the end() iterator, are invalidated. No references are invalidated.

Parameters

args - arguments to forward to the constructor of the element
Type requirements
-T (the container's element type) must meet the requirements of EmplaceConstructible.

Return value

(none) (until C++17)
A reference to the inserted element. (since C++17)

Complexity

Constant.

Exceptions

If an exception is thrown, this function has no effect (strong exception guarantee).

See also

inserts an element to the beginning
(public member function)

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