template< class... Args > void emplace( Args&&... args ); | (since C++11) (until C++17) | |
template< class... Args > decltype(auto) emplace( Args&&... args ); | (since C++17) |
Pushes a new element to the end of the queue. The element is constructed in-place, i.e. no copy or move operations are performed. The constructor of the element is called with exactly the same arguments as supplied to the function.
Effectively calls c.emplace_back(std::forward<Args>(args)...);
| args | - | arguments to forward to the constructor of the element |
| (none) | (until C++17) |
The value or reference, if any, returned by the above call to Container::emplace_back. | (since C++17) |
Identical to the complexity of Container::emplace_back.
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 2783 | C++17 | emplace returned reference, breaking compatibility with pre-C++17 containers | returns decltype(auto) |
| inserts element at the end (public member function) |
|
| removes the first element (public member function) |
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