operator+, operator-(std::basic_const_iterator)

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Iterator library
Iterator concepts
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friend constexpr basic_const_iterator

    operator+( const basic_const_iterator& i, difference_type n )

        requires std::random_access_iterator<Iter>;
(1) (since C++23)
friend constexpr basic_const_iterator

    operator+( difference_type n, const basic_const_iterator& i )

        requires std::random_access_iterator<Iter>;
(2) (since C++23)
friend constexpr basic_const_iterator

    operator-( const basic_const_iterator& i, difference_type n )

        requires std::random_access_iterator<Iter>;
(3) (since C++23)

Returns the iterator i incremented or decremented by n.

1,2) Returns an iterator which is advanced by n positions.
3) Returns an iterator which is advanced by -n positions.

These functions are not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when std::basic_const_iterator<Iter> is an associated class of the arguments..

Return value

1,2) basic_const_iterator(i.base() + n)
3) basic_const_iterator(i.base() - n)

Example