std::ranges::enumerate_view<V>::iterator<Const>::operator++,--,+=,-=
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                    |   constexpr /*iterator*/& operator++();  | 
(1) | (since C++23) | 
|   constexpr void operator++( int );  | 
(2) | (since C++23) | 
|   constexpr /*iterator*/ operator++( int ) requires ranges::forward_range<Base>;  | 
(3) | (since C++23) | 
|   constexpr /*iterator*/& operator--() requires ranges::bidirectional_range<Base>;  | 
(4) | (since C++23) | 
|   constexpr /*iterator*/ operator--( int ) requires ranges::bidirectional_range<Base>;  | 
(5) | (since C++23) | 
|   constexpr /*iterator*/& operator+=( difference_type n ) requires ranges::random_access_range<Base>;  | 
(6) | (since C++23) | 
|   constexpr /*iterator*/& operator-=( difference_type n ) requires ranges::random_access_range<Base>;  | 
(7) | (since C++23) | 
Increments or decrements the iterator.
Let current_ be the underlying iterator and pos_ be the underlying index.
1) Equivalent to ++current_; ++pos_; return *this;
2) Equivalent to ++current_;
3) Equivalent to auto tmp = *this; ++*this; return tmp;
4) Equivalent to --current_; --pos_; return *this;
5) Equivalent to auto tmp = *this; --*this; return tmp;
6) Equivalent to current_ += n; pos_ += n; return *this;
7) Equivalent to current_ -= n; pos_ -= n; return *this;
Parameters
| n | - | position relative to current location | 
Return value
1,4,6,7) *this
2) (none)
3,5) a copy of *this that was made before the change
See also
|    (C++23)  | 
  performs iterator arithmetic  (function)  |