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

 

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std::deque

Member types
Member functions
deque::deque deque::~deque deque::operator= deque::assign deque::assign_range (C++23)   deque::get_allocator Element access deque::at deque::operator[] deque::front deque::back Iterators deque::begindeque::cbegin (C++11) deque::enddeque::cend (C++11) deque::rbegindeque::crbegin (C++11) deque::renddeque::crend (C++11)	Capacity deque::empty deque::size deque::max_size deque::shrink_to_fit (DR*) Modifiers deque::clear deque::insert deque::insert_range (C++23) deque::emplace deque::erase deque::push_front deque::emplace_front (C++11) deque::prepend_range (C++23) deque::pop_front deque::push_back deque::emplace_back (C++11) deque::append_range (C++23) deque::pop_back deque::resize deque::swap
Non-member functions
operator==operator<=> (C++20) swap(std::deque) erase(std::deque)erase_if(std::deque) (C++20)(C++20)	operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
Deduction guides(C++17)

 

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) (constexpr since C++26)

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
- If T is not EmplaceConstructible into deque from args..., the behavior is undefined.

Return value

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

Complexity

Constant.

Exceptions

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

See also

push_front

inserts an element to the beginning (public member function)