multiset::emplace

Article
07/29/2015

Inserts an element constructed in place (no copy or move operations are performed), with a placement hint.

template<class... Args>
   iterator emplace(
      Args&&... args);

Parameters

Parameter	Description
args	The arguments forwarded to construct an element to be inserted into the multiset.

Return Value

An iterator to the newly inserted element.

Remarks

No references to container elements are invalidated by this function, but it may invalidate all iterators to the container.

During emplacement, if an exception is thrown, the container's state is not modified.

Example

// multiset_emplace.cpp
// compile with: /EHsc
#include <set>
#include <string>
#include <iostream>

using namespace std;

template <typename S> void print(const S& s) {
    cout << s.size() << " elements: ";

    for (const auto& p : s) {
        cout << "(" << p << ") ";
    }

    cout << endl;
}

int main()
{
    multiset<string> s1;

    s1.emplace("Anna");
    s1.emplace("Bob");
    s1.emplace("Carmine");

    cout << "multiset modified, now contains ";
    print(s1);
    cout << endl;

    s1.emplace("Bob");

    cout << "multiset modified, now contains ";
    print(s1);
    cout << endl;
}

Output

multiset modified, now contains 3 elements: (Anna) (Bob) (Carmine)

multiset modified, now contains 4 elements: (Anna) (Bob) (Bob) (Carmine)

Requirements

Header: <set>

Namespace: std

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