std::deque::emplace_front
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| 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)....
| Contents | 
[edit] Parameters
| args | - | arguments to forward to the constructor of the element | 
| Type requirements | ||
| - T (the container's element type)must meet the requirements ofEmplaceConstructible. | ||
[edit] Return value
| (none) | (until C++17) | 
| A reference to the inserted element. | (since C++17) | 
[edit] Complexity
Constant.
[edit] Exceptions
If an exception is thrown, this function has no effect (strong exception guarantee).
[edit] See also
| inserts an element to the beginning (public member function) | 


