std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::value_compare

 

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std::flat_map

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flat_map::flat_map flat_map::operator= Element access flat_map::at flat_map::operator[] Iterators flat_map::beginflat_map::cbegin flat_map::endflat_map::cend flat_map::rbeginflat_map::crbegin flat_map::rendflat_map::crend Lookup flat_map::count flat_map::find flat_map::contains flat_map::equal_range    flat_map::lower_bound flat_map::upper_bound Capacity flat_map::size flat_map::max_size flat_map::empty Modifiers flat_map::clear flat_map::erase flat_map::swap flat_map::emplace flat_map::extract flat_map::replace flat_map::insert flat_map::insert_range flat_map::insert_or_assign flat_map::emplace_hint flat_map::try_emplace Observers flat_map::key_comp flat_map::keys flat_map::value_comp flat_map::values

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operator==operator<=>         swap(std::flat_map) erase_if(std::flat_map)

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uses_allocator<std::flat_map>

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sorted_unique       sorted_unique_t

Deduction guides

 

class value_compare;		(since C++23)

std::flat_map::value_compare is a function object that compares objects of type std::flat_map::const_reference (a pair of references to the stored key/value) by comparing the first components (i.e. keys) of the passed pairs.

Member objects

Member name	Definition
comp(private)	the comparison function object of type std::flat_map::key_compare (exposition-only member object*)

Member functions

(constructor) (private)	constructs value_compare object (public member function)
operator()	compares two values of type value_type (public member function)

std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::value_compare::value_compare

private: value_compare( key_compare c );		(exposition only*)

Initializes the underlying instance of the comparator comp to c.

Parameters

c

-

a comparator to assign

std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::value_compare::operator()

bool operator()(const const_reference& lhs, const const_reference& rhs )const;

Compares lhs.first and rhs.first by calling the stored comparator comp.

Parameters

lhs, rhs

-

values to compare

Return value

comp(lhs.first, rhs.first)

Exceptions

May throw implementation-defined exceptions.