How do I use map::emplace in C++11?

Can you explain how to use map::emplace in C++11?

Sure! The map::emplace function allows you to insert elements into a map by constructing them in place, which can be more efficient than using insert.

What are the advantages of using emplace over insert?

Using emplace can avoid unnecessary copies or moves of objects, as it constructs the element directly in the map.

Can you give me a code example of map::emplace?

Certainly! Here's a simple example:

std::map<int, std::string> myMap;
myMap.emplace(1, "one");
myMap.emplace(2, "two");

This will insert the pairs (1, "one") and (2, "two") into the map.

Are there any limitations to using emplace?

Yes, emplace requires that the key and value types are constructible in place, so you need to ensure that the arguments you pass can be used to construct the types.