deduction guides for std::flat_multiset

From cppreference.com

Defined in header <flat_set>
template < class KeyContainer,

class Compare = std::less < typename KeyContainer:: value_type > >
flat_multiset( KeyContainer, Compare = Compare( ) )

- > flat_multiset< typename KeyContainer:: value_type, Compare, KeyContainer> ;
(1) (since C++23)
template < class KeyContainer, class Allocator >

flat_multiset( KeyContainer, Allocator )
- > flat_multiset< typename KeyContainer:: value_type,

std::less < typename KeyContainer:: value_type >, KeyContainer> ;
(2) (since C++23)
template < class KeyContainer, class Compare, class Allocator >

flat_multiset( KeyContainer, Compare, Allocator )

- > flat_multiset< typename KeyContainer:: value_type, Compare, KeyContainer> ;
(3) (since C++23)
template < class KeyContainer,

class Compare = std::less < typename KeyContainer:: value_type > >
flat_multiset( std::sorted_equivalent_t, KeyContainer, Compare = Compare( ) )

- > flat_multiset< typename KeyContainer:: value_type, Compare, KeyContainer> ;
(4) (since C++23)
template < class KeyContainer, class Allocator >

flat_multiset( std::sorted_equivalent_t, KeyContainer, Allocator )
- > flat_multiset< typename KeyContainer:: value_type,

std::less < typename KeyContainer:: value_type >, KeyContainer> ;
(5) (since C++23)
template < class KeyContainer, class Compare, class Allocator >

flat_multiset( std::sorted_equivalent_t, KeyContainer, Compare, Allocator )

- > flat_multiset< typename KeyContainer:: value_type, Compare, KeyContainer> ;
(6) (since C++23)
template < class InputIter,

class Compare = std::less < /*iter-value-type*/ <InputIter>> >
flat_multiset( InputIter, InputIter, Compare = Compare( ) )

- > flat_multiset< /*iter-value-type*/ <InputIter>, Compare> ;
(7) (since C++23)
template < class InputIter,

class Compare = std::less < /*iter-value-type*/ <InputIter>> >
flat_multiset( std::sorted_equivalent_t, InputIter, InputIter, Compare = Compare( ) )

- > flat_multiset< /*iter-value-type*/ <InputIter>, Compare> ;
(8) (since C++23)
template < ranges::input_range R,

class Compare = std::less < ranges::range_value_t <R>>,
class Allocator = std::allocator < ranges::range_value_t <R>> >
flat_multiset( std::from_range_t, R&&, Compare = Compare( ), Allocator = Allocator( ) )
- > flat_multiset< ranges::range_value_t <R>, Compare,
std::vector < ranges::range_value_t <R>,

/*alloc-rebind*/ <Allocator, ranges::range_value_t <R>>>> ;
(9) (since C++23)
template < ranges::input_range R, class Allocator >

flat_multiset( std::from_range_t, R&&, Allocator )
- > flat_multiset< ranges::range_value_t <R>, std::less < ranges::range_value_t <R>>,
std::vector < ranges::range_value_t <R>,

/*alloc-rebind*/ <Allocator, ranges::range_value_t <R>>>> ;
(10) (since C++23)
template < class Key, class Compare = std::less <Key> >

flat_multiset( std::initializer_list <Key>, Compare = Compare( ) )

- > flat_multiset<Key, Compare> ;
(11) (since C++23)
template < class Key, class Compare = std::less <Key> >

flat_multiset( std::sorted_equivalent_t,
std::initializer_list <Key>, Compare = Compare( ) )

- > flat_multiset<Key, Compare> ;
(12) (since C++23)

These deduction guides are provided for to allow deduction from:

1) A container and a comparator.
2) A container and an allocator.
3) A container, a comparator and an allocator.
4) The std::sorted_equivalent_t tag, a container and a comparator.
5) The std::sorted_equivalent_t tag, a container and an allocator.
6) The std::sorted_equivalent_t tag, a container, a comparator and an allocator.
7) An iterator range and a comparator.
8) The std::sorted_equivalent_t tag, an iterator range and a comparator.
10) The std::from_range_t tag, an input_range
11) The std::initializer_list and a comparator.
12) The std::sorted_equivalent_t tag, the std::initializer_list

These overloads participate in overload resolution only if InputIt satisfies LegacyInputIterator, Alloc satisfies Allocator, and Comp does not satisfy 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 { } )

Example