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deductiongu...red_multiset(3)  C++ Standard Libary deductiongu...red_multiset(3)

NAME
     deductionguidesforstd::unordered_multiset	  -   deductionguidesforstd::un-
     ordered_multiset

Synopsis
	Defined in header <unordered_set>
	template<

	    class InputIt,
	    class Hash = std::hash<typename
	std::iterator_traits<InputIt>::value_type>,
	    class Pred = std::equal_to<typename
	std::iterator_traits<InputIt>::value_type>,
	    class Alloc = std::allocator<typename
	std::iterator_traits<InputIt>::value_type>  >			     (1)
     (since C++17)
	unordered_multiset( InputIt, InputIt,
			    typename /* see below */::size_type = /* see
	below */,
			    Hash = Hash(), Pred = Pred(), Alloc = Alloc()
	)
	    -> unordered_multiset<typename
	std::iterator_traits<InputIt>::value_type,

				  Hash, Pred, Alloc>;
	template< class T,

		  class Hash = std::hash<T>,
		  class Pred = std::equal_to<T>,
		  class Alloc = std::allocator<T> >
	unordered_multiset(   std::initializer_list<T>, 		     (2)
     (since C++17)
			    typename /* see below */::size_type = /* see
	below */,
			    Hash = Hash(), Pred = Pred(), Alloc = Alloc()
	)

	    -> unordered_multiset<T, Hash, Pred, Alloc>;
	template< class InputIt, class Alloc >

	unordered_multiset( InputIt, InputIt, typename /* see below
	*/::size_type, Alloc )
	    -> unordered_multiset<typename
	std::iterator_traits<InputIt>::value_type,			     (3)
     (since C++17)
				  std::hash<typename
	std::iterator_traits<InputIt>::value_type>,
				  std::equal_to<typename
	std::iterator_traits<InputIt>::value_type>,

				  Alloc>;
	template< class InputIt, class Hash, class Alloc >

	unordered_multiset( InputIt, InputIt, typename /* see below
	*/::size_type, Hash, Alloc )
	    ->	 unordered_multiset<typename				     (4)
     (since C++17)
	std::iterator_traits<InputIt>::value_type, Hash,
				  std::equal_to<typename
	std::iterator_traits<InputIt>::value_type>,

				  Alloc>;
	template< class T, class Alloc >

	unordered_multiset( std::initializer_list<T>, typename /* see
	below */::size_type,  Alloc  )					     (5)
     (since C++17)

	    -> unordered_multiset<T, std::hash<T>, std::equal_to<T>,
	Alloc>;
	template< class T, class Hash, class Alloc >

	unordered_multiset( std::initializer_list<T>, typename /* see
	below	*/::size_type,						     (6)
     (since C++17)
			    Hash, Alloc )

	    -> unordered_multiset<T, Hash, std::equal_to<T>, Alloc>;
	template< ranges::input_range R,

		  class Hash = std::hash<ranges::range_value_t<R>>,
		  class Pred = std::equal_to<ranges::range_value_t<R>>,
		  class Alloc = std::allocator<ranges::range_value_t<R>>
	>
	unordered_multiset(  std::from_range_t,  R&&,			     (7)
     (since C++23)
			    typename /* see below */::size_type = /* see
	below */,
			    Hash = Hash(), Pred = Pred(), Alloc = Alloc()
	)

	    -> unordered_multiset<ranges::range_value_t<R>, Hash, Pred,
	Alloc>;
	template< ranges::input_range R, class Alloc >

	unordered_multiset( std::from_range_t, R&&,
			    typename /* see below */::size_type, Alloc )
	    ->	 unordered_multiset<ranges::range_value_t<R>,		     (8)
     (since C++23)
	hash<ranges::range_value_t<R>>,

	std::equal_to<ranges::range_value_t<R>>, Alloc>;
	template< ranges::input_range R, class Alloc >

	unordered_multiset( std::from_range_t, R&&, Alloc )
	    ->	unordered_multiset<ranges::range_value_t<R>,		     (9)
     (since C++23)
	hash<ranges::range_value_t<R>>,

	std::equal_to<ranges::range_value_t<R>>, Alloc>;
	template< ranges::input_range R, class Hash, class Alloc >

	unordered_multiset( std::from_range_t, R&&,
			    typename /* see below */::size_type, Hash,
	Alloc  )							    (10)
     (since C++23)
	    -> unordered_multiset<ranges::range_value_t<R>, Hash,

	std::equal_to<ranges::range_value_t<R>>, Alloc>;

	1-6) These deduction guides are provided for unordered_multiset to allow
     deduction
	from an iterator range	(overloads  (1,3,4))  and  std::initializer_list
     (overloads
	(2,5,6)).  This overload participates in overload resolution only if In-
     putIt
	satisfies LegacyInputIterator, Alloc satisfies Allocator,  neither  Hash
     nor Pred
	satisfy Allocator, Hash is not an integral type.
	7-10)  These deduction guides are provided for unordered_multiset to al-
     low deduction
	from a std::from_range_t tag and an input_range.

	Note: the extent to which the library determines that a  type  does  not
     satisfy
	LegacyInputIterator  is  unspecified,  except that as a minimum integral
     types do not
	qualify as input iterators. Likewise, the extent to which it  determines
     that a type
	does  not satisfy Allocator is unspecified, except that as a minimum the
     member type
	Alloc::value_type must exist and the expression
	std::declval<Alloc&>().allocate(std::size_t{}) must be well-formed  when
     treated as
	an unevaluated operand.

	The  size_type	parameter  type  in these guides refers to the size_type
     member type of
	the type deduced by the deduction guide.

Notes
	    Feature-test macro	     Value    Std		    Feature
	__cpp_lib_containers_ranges 202202L  (C++23)  Ranges-aware  construction
     and insertion;
						    overloads (7-10)

Example
     // Run this code

      #include <unordered_set>

      int main()
      {
	  // guide #2 deduces std::unordered_multiset<int>
	  std::unordered_multiset s = {1, 2, 3, 4};

	  // guide #1 deduces std::unordered_multiset<int>
	  std::unordered_multiset s2(s.begin(), s.end());
      }

http://cppreference.com 	   2024.06.10	   deductiongu...red_multiset(3)
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