std::queue emplace() method
- od C++17
- od C++11
// Non const version only
template< class... Args >
decltype(auto) emplace( Args&&... args );
// Non const version only
template< class... Args >
void emplace( Args&&... args );
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.
zanotuj
Effectively calls c.emplace_back(std::forward<Args>(args)...)
.
Parameters
args
- arguments to forward to the constructor of the element
Return value
- od C++17
- do C++17
(none)
The value or reference, if any, returned by the above call to the underlying container's
emplace_back
.Complexity
Equivalent to that of emplace_back
of the underlying container.
Example
Main.cpp
#include <iostream>
#include <queue>
struct S
{
int id;
S(int i, double d, std::string s) : id{i}
{
std::cout << "S::S(" << i << ", " << d << ", \"" << s << "\");\n";
}
};
int main()
{
std::queue<S> adaptor;
const S& s = adaptor.emplace(42, 3.14, "C++"); // for return value C++17 required
std::cout << "id = " << s.id << '\n';
}
Output
S::S(42, 3.14, "C++")
id = 42