std::flat_set<Key,Compare,KeyContainer>::empty

 

C++

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Technical specifications

Symbols index

External libraries

 

Containers library

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array (C++11)

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vector<bool>

inplace_vector (C++26)

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list

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unordered_set (C++11)

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stack

queue

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flat_set (C++23)

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std::flat_set

Member types

Member functions

flat_set::flat_set flat_set::operator= Iterators flat_set::beginflat_set::cbegin flat_set::endflat_set::cend flat_set::rbeginflat_set::crbegin flat_set::rendflat_set::crend Capacity flat_set::size flat_set::max_size flat_set::empty Observers flat_set::key_comp flat_set::value_comp      Modifiers flat_set::clear flat_set::insert flat_set::insert_range flat_set::emplace flat_set::emplace_hint flat_set::erase flat_set::swap flat_set::extract flat_set::replace Lookup flat_set::count flat_set::find flat_set::contains flat_set::equal_range flat_set::lower_bound flat_set::upper_bound Non-member functions operator==operator<=> swap(std::flat_set) erase_if(std::flat_set)

Helper classes

uses_allocator<std::flat_set>

Tags

sorted_unique      sorted_unique_t

Deduction guides

 

bool empty() const noexcept;		(since C++23)

Checks if the container has no elements, i.e. whether begin() == end().

Parameters

(none)

Return value

true if the container is empty, false otherwise.

Complexity

Constant.

Example

Template:cpp/container/flat set/example empty

See also

size	returns the number of elements (public member function)
empty (C++17)	checks whether the container is empty (function template)