std::unordered_set::emplace

From Cppreference

C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Containers library
array (C++11) vector deque forward_list (C++11) list set multiset map multimap unordered_set (C++11) unordered_multiset (C++11) unordered_map (C++11) unordered_multimap (C++11) stack queue priority_queue
std::unordered_set
Member functions unordered_set::unordered_set unordered_set::~unordered_set unordered_set::operator= unordered_set::get_allocator Iterators unordered_set::begin unordered_set::cbegin unordered_set::end unordered_set::cend Capacity unordered_set::erase unordered_set::size unordered_set::max_size Modifiers unordered_set::clear unordered_set::insert unordered_set::emplace unordered_set::emplace_hint unordered_set::erase unordered_set::swap Lookup unordered_set::count unordered_set::find unordered_set::equal_range Bucket interface unordered_set::begin(int) unordered_set::end(int) unordered_set::bucket_count unordered_set::max_bucket_count unordered_set::bucket_size unordered_set::bucket Hash policy unordered_set::load_factor unordered_set::max_load_factor unordered_set::rehash unordered_set::reserve Observers unordered_set::hash_function unordered_set::key_eq

template <class... Args> std::pair<iterator, bool> emplace( Args&&... args );		(since C++11)

Inserts a new element to the container. 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.

If rehashing occurs due to the insertion, all iterators are invalidated. Otherwise iterators are not affected. References are not invalidated.

This section is incomplete Reason: when rehashing occurs?

Contents 1 Parameters 2 Return value 3 Complexity 4 See also

[edit] Parameters

args

-

arguments to forward to the constructor of the element

[edit] Return value

returns a pair consisting of a bool denoting whether the insertion took place and an iterator to the inserted element.

[edit] Complexity

This section is incomplete

[edit] See also

emplace_hint	constructs elements in-place using a hint (public member function)
insert	inserts elements (public member function)