home | help 
deductionguidesforstd::set(3)  C++ Standard Libary deductionguidesforstd::set(3)

NAME
     deductionguidesforstd::set - deductionguidesforstd::set

Synopsis
	Defined in header <set>
	template<

	    class InputIt,
	    class Comp = std::less<typename
	std::iterator_traits<InputIt>::value_type>,
	    class  Alloc  = std::allocator<typename			     (1)
     (since C++17)
	std::iterator_traits<InputIt>::value_type>>
	set( InputIt, InputIt, Comp = Comp(), Alloc = Alloc() )

	    -> set<typename std::iterator_traits<InputIt>::value_type,
	Comp, Alloc>;
	template<

	    class Key, class Comp = std::less<Key>,
	    class Alloc = std::allocator<Key>  >			     (2)
     (since C++17)
	set( std::initializer_list<Key>, Comp = Comp(), Alloc = Alloc() )

	    -> set<Key, Comp, Alloc>;
	template< class InputIt, class Alloc >

	set( InputIt, InputIt, Alloc )
	    ->	set<typename  std::iterator_traits<InputIt>::value_type,     (3)
     (since C++17)

		   std::less<typename
	std::iterator_traits<InputIt>::value_type>, Alloc>;
	template< class Key, class Alloc >

	set( std::initializer_list<Key>, Alloc	)			     (4)
     (since C++17)

	    -> set<Key, std::less<Key>, Alloc>;
	template< ranges::input_range R, class Compare =
	less<ranges::range_value_t<R>>,

		  class  Alloc	= std::allocator<ranges::range_value_t<R>> > (5)
     (since C++23)
	set( std::from_range_t, R&&, Compare = Compare(), Alloc = Alloc()
	)

	    -> set<ranges::range_value_t<R>, Compare, Alloc>;
	template< ranges::input_range R, class Alloc >

	set( std::from_range_t, R&&, Alloc  )				     (6)
     (since C++23)

	    -> set<ranges::range_value_t<R>,
	std::less<ranges::range_value_t<R>>, Alloc>;

	1-4) These deduction guides are provided for set to allow deduction from
     an iterator
	range (overloads (1,3)) and std::initializer_list (overloads (2,4)).
	5,6) These deduction guides are provided for set to allow deduction from
     a
	std::from_range_t tag and an input_range.

	These  overloads participate in overload resolution only if InputIt sat-
     isfies
	LegacyInputIterator, Alloc satisfies Allocator, and Comp does  not  sat-
     isfy Allocator.

	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.

Notes
	    Feature-test macro	     Value    Std		    Feature
	__cpp_lib_containers_ranges 202202L  (C++23)  Ranges-aware  construction
     and insertion;
						    overload (5,6)

Example
     // Run this code

      #include <set>

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

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

http://cppreference.com 	   2024.06.10	   deductionguidesforstd::set(3)
home | help