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std::unorde...set::emplace(3)  C++ Standard Libary std::unorde...set::emplace(3)

NAME
     std::unordered_set::emplace - std::unordered_set::emplace

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

	Inserts  a  new element into the container constructed in-place with the
     given args,
	if there is no element with the key in the container.

	The constructor of the new element is called with exactly the same argu-
     ments as
	supplied to emplace, forwarded via std::forward<Args>(args).... The ele-
     ment may be
	constructed even if there already is an element with the key in the con-
     tainer, in
	which case the newly constructed element will be destroyed immediately.

	Careful use of emplace allows the new element to  be  constructed  while
     avoiding
	unnecessary copy or move operations.

	If after the operation the new number of elements is greater than old
	max_load_factor() * bucket_count() a rehashing takes place.
	If  rehashing  occurs  (due to the insertion), all iterators are invali-
     dated. Otherwise
	(no rehashing), iterators are not invalidated.

Parameters
	args - arguments to forward to the constructor of the element

Return value
	A pair consisting of an iterator to the inserted element (or to the ele-
     ment that
	prevented the insertion) and a bool value set to true if and only if the
     insertion
	took place.

Exceptions
	If an exception is thrown for any reason, this function  has  no  effect
     (strong
	exception safety guarantee).

Complexity
	Amortized constant on average, worst case linear in the size of the con-
     tainer.

Example
	 This section is incomplete
	 Reason: no example

See also
	emplace_hint constructs elements in-place using a hint
		     (public member function)
		     inserts elements
	insert	     or nodes
		     (since C++17)
		     (public member function)

Category:
	  * Todo no example

http://cppreference.com 	   2024.06.10	   std::unorde...set::emplace(3)
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