std::reverse_iterator<Iter>::base

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std::reverse_iterator

Member functions
reverse_iterator::reverse_iterator
reverse_iterator::operator=
reverse_iterator::base
reverse_iterator::operator*reverse_iterator::operator->
reverse_iterator::operator[]
reverse_iterator::operator++reverse_iterator::operator+reverse_iterator::operator+=reverse_iterator::operator--reverse_iterator::operator-reverse_iterator::operator-=
Non-member functions
operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20)
operator+
operator-
iter_move (C++20)
iter_swap (C++20)
make_reverse_iterator (C++14)

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iterator_type base()const;		(constexpr since C++17)

Returns the underlying iterator.

[edit]Return value

current

[edit]Notes

The base iterator refers to the element that is next (from theiterator_type perspective) to the element thereverse_iterator is currently pointing to. That is&*(this->base()-1)==&*(*this).

[edit]Example

Run this code

#include <iostream>#include <iterator>#include <vector> int main(){std::vector<int> v={0,1,2,3,4,5}; using RevIt=std::reverse_iterator<std::vector<int>::iterator>; constauto it= v.begin()+3;    RevIt r_it{it}; std::cout<<"*it == "<<*it<<'\n'<<"*r_it == "<<*r_it<<'\n'<<"*r_it.base() == "<<*r_it.base()<<'\n'<<"*(r_it.base() - 1) == "<<*(r_it.base()-1)<<'\n';     RevIt r_end{v.begin()};    RevIt r_begin{v.end()}; for(auto it= r_end.base(); it!= r_begin.base();++it)std::cout<<*it<<' ';std::cout<<'\n'; for(auto it= r_begin; it!= r_end;++it)std::cout<<*it<<' ';std::cout<<'\n';}

Output:

*it == 3*r_it == 2*r_it.base() == 3*(r_it.base() - 1) == 20 1 2 3 4 55 4 3 2 1 0

[edit]See also

operator*operator->

accesses the pointed-to element
(public member function)[edit]

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std::reverse_iterator<Iter>::base

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