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std::revers...erator::base(3)  C++ Standard Libary std::revers...erator::base(3)

NAME
     std::reverse_iterator::base - std::reverse_iterator::base

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

	Returns  the  underlying  base	iterator.  That  is  std::reverse_itera-
     tor(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.

Parameters
	(none)

Return value
	The underlying iterator.

Exceptions
	May throw implementation-defined exceptions.

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>;

	  const auto 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) == 2
      0 1 2 3 4 5
      5 4 3 2 1 0

See also
	operator*  accesses the pointed-to element
	operator-> (public member function)

http://cppreference.com 	   2024.06.10	   std::revers...erator::base(3)
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