std::list<T,Allocator>::emplace (3) - Linux Manuals
template< class... Args > (since C++11)
iterator emplace( const_iterator pos, Args&&... args );
Inserts a new element into the container directly before pos. The element is constructed through std::allocator_traits::construct, which typically uses placement-new to construct the element in-place at a location provided by the container. The arguments args... are forwarded to the constructor as std::forward<Args>(args)....
No iterators or references are invalidated.
T (the container's element type) must meet the requirements of EmplaceConstructible.
Iterator pointing to the emplaced element.
If an exception is thrown (e.g. by the constructor), the container is left unmodified, as if this function was never called (strong exception guarantee).
insert (public member function)