std::ranges::chunk_view<V>::iterator<Const>::operator++,--,+=,-=

constexpr /*iterator*/& operator++();
 (1) (since C++23) 
constexpr /*iterator*/ operator++( int );
 (2) (since C++23) 
constexpr /*iterator*/& operator--()
    requires ranges::bidirectional_range<Base>;
 (3) (since C++23) 
constexpr /*iterator*/ operator--( int )
    requires ranges::bidirectional_range<Base>;
 (4) (since C++23) 
constexpr /*iterator*/& operator+=( difference_type x )
    requires ranges::random_access_range<Base>;
 (5) (since C++23) 
constexpr /*iterator*/& operator-=( difference_type x )
    requires ranges::random_access_range<Base>;
 (6) (since C++23)

Advances or decrements the iterator.

Let current_, end_, and n_ be the underlying data members of chunk_view::iterator.

1) Equivalent to: 
missing_ = ranges::advance(current_, n_, end_);
return *this;
Before the invocation the expression current_ != end_ must be true, otherwise the behavior is undefined.
2) Equivalent to: auto tmp = *this; ++*this; return tmp;.
3) Equivalent to: 
ranges::advance(current_, missing_ - n_);
missing_ = 0;
return *this;
4) Equivalent to: auto tmp = *this; --*this; return tmp;.
5) Equivalent to: 
if (x > 0)
{
    ranges::advance(current_, n_ * (x - 1));
    missing_ = ranges::advance(current_, n_, end_);
}
else if (x < 0)
{
    ranges::advance(current_, n_ * x + missing_);
    missing_ = 0;
}
return *this;
If x is positive, then before the invocation the expression ranges::distance(current_, end_) > n_ * (x - 1) must be true (i.e., informally, the requested chunk should be "inside" the underlying sequence). If x is negative, this precondition is always met.
6) Equivalent to: return *this += -x;.

Parameters

x - a position relative to current location

Return value

1,3,5,6) *this
2,4) a copy of *this that was made before the change

Example

See also

(C++23)
 performs iterator arithmetic
(function)

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