Namespaces
Variants
Views
Actions

std::reverse_iterator::base

From cppreference.com
 
 
 
 
Iterator base() const;
(until C++17)
constexpr Iterator base() const;
(since C++17)

Returns the underlying base iterator. That is std::reverse_iterator(it).base() == it.

The base iterator refers to the element that is next (from the std::reverse_iterator::iterator_type perspective) to the element the reverse_iterator is currently pointing to. That is &*(rit.base() - 1) == &*rit.

Contents

[edit] Parameters

(none)

[edit] Return value

The underlying iterator.

[edit] Exceptions

(none)

[edit] Example

#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>;
  {
    const auto it = v.begin() + 3;
    RevIt r_it(it);
 
    std::cout << "*it == " << *it << ", *r_it.base() == " << *r_it.base()
    << '\n' << "*r_it == " << *r_it <<", *(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";
  }
}

Output:

*it == 3, *r_it.base() == 3
*r_it == 2, *(r_it.base()-1) == 2
0 1 2 3 4 5

[edit] See also

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