std::deque emplace_front() method
- od C++17
- od C++11
template< class... Args >
reference emplace_front( Args&&... args );
// Non const version only
template< class... Args >
void emplace_front( Args&&... args );
Prepends a new element at the beginnign of the container.
The element is constructed through std::allocator_traits<Alloc>::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)....
Invalidation
All iterators, including the past-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 ofEmplaceConstructible.
Return value
- od C++17
- do C++17
A reference to the inserted element.
(none)
Complexity
Constant - O(1).
Exceptions
If an exception is thrown, this function has no effect (strong exception guarantee).
Example
important
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