std::forward_list<T,Allocator>::before_begin, cbefore_begin

 

C++

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node-handle (C++17)

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forward_list (C++11)

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std::forward_list

Member functions
forward_list::forward_list forward_list::~forward_list forward_list::operator= forward_list::assign forward_list::assign_range (C++23)   forward_list::get_allocator Element access forward_list::front Iterators forward_list::before_beginforward_list::cbefore_begin forward_list::beginforward_list::cbegin forward_list::endforward_list::cend Capacity forward_list::empty forward_list::max_size	Modifiers forward_list::clear forward_list::emplace_front forward_list::push_front forward_list::insert_after forward_list::emplace_after forward_list::erase_after forward_list::insert_range_after (C++23) forward_list::prepend_range (C++23) forward_list::pop_front forward_list::resize forward_list::swap Operations forward_list::merge forward_list::splice_after forward_list::removeforward_list::remove_if forward_list::reverse forward_list::unique forward_list::sort
Non-member functions
operator==operator<=> (C++20) swap(std::forward_list) erase(std::forward_list)erase_if(std::forward_list) (C++20)(C++20)	operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
Deduction guides (C++17)

 

iterator before_begin() noexcept;	(1)	(since C++11) (constexpr since C++26)
const_iterator before_begin() const noexcept;	(2)	(since C++11) (constexpr since C++26)
const_iterator cbefore_begin() const noexcept;	(3)	(since C++11) (constexpr since C++26)

Returns a non-dereferenceable iterator, incrementing the before-begin iterator gives exactly the same iterator as obtained from begin()/cbegin().

The only usage cases are in functions insert_after(), emplace_after(), erase_after(), splice_after() and the increment operator.

Return value

An iterator representing the position right before the begin iterator.

Complexity

Constant.

Example

See also

begincbegin	returns an iterator to the beginning (public member function)
endcend	returns an iterator to the end (public member function)

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