std::ranges::join_with_view<V,Pattern>::iterator<Const>::operator++,--

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< cpp‎ | ranges‎ | join with view‎ | iterator
C++
Ranges library
Range adaptors
std::ranges::join_with_view
constexpr /*iterator*/ & operator++ ( ) ;
(1) (since C++23)
constexpr void operator++ ( int ) ;
(2) (since C++23)
constexpr /*iterator*/ operator++ ( int )

requires std::is_reference_v < /*InnerBase*/ > &&
ranges::forward_range < /*Base*/ > &&

ranges::forward_range < /*InnerBase*/ > ;
(3) (since C++23)
constexpr /*iterator*/ & operator-- ( )

requires std::is_reference_v < /*InnerBase*/ > &&
ranges::bidirectional_range < /*Base*/ > &&
ranges::bidirectional_range < /*InnerBase*/ > &&
ranges::common_range < /*InnerBase*/ > &&
ranges::bidirectional_range < /*PatternBase*/ > &&

ranges::common_range < /*PatternBase*/ > ;
(4) (since C++23)
constexpr /*iterator*/ operator-- ( int )

requires std::is_reference_v < /*InnerBase*/ > &&
ranges::bidirectional_range < /*Base*/ > &&
ranges::bidirectional_range < /*InnerBase*/ > &&
ranges::common_range < /*InnerBase*/ > &&
ranges::bidirectional_range < /*PatternBase*/ > &&

ranges::common_range < /*PatternBase*/ > ;
(5) (since C++23)

Increments or decrements the iterator.

1) Increments the inner iterator as if by std::visit ( [ ] ( auto & it) { ++it; } inner_it_ );
After that, adjusts the inner and outer iterators as follows:
  • If the incremented inner iterator is the past-the-end iterator of the pattern range, it is set to an iterator to the beginning of the next inner range.
  • If the incremented inner iterator is the past-the-end iterator of an inner range, the outer iterator is incremented. Then:
  • If the incremented outer iterator is not the past-the-end iterator of the outer range, the inner iterator is set to an iterator to the beginning of the pattern range.
  • Otherwise, if std::is_reference_v< InnerBase > is true, the inner iterator is set to a pattern iterator holding a singular value
  • Repeats the operations above until either the inner iterator is not a past-the-end iterator, or the outer iterator is a past-the-end iterator.
2) Equivalent to ++*this;.
3) Equivalent to auto tmp = *this;
++*this;
return tmp;
4) If the outer iterator is the past-the-end iterator of the outer range, decrements it and sets the inner iterator to the past-the-end iterator of the last inner range, otherwise do nothing.
After that, adjusts the inner and outer iterators as follows:
  • If the inner iterator refers to the beginning of an inner range, it is set to the past-the-end iterator of the pattern range.
  • If the inner iterator refers to the beginning of the pattern range, the outer iterator is decremented, and the inner iterator is set to the past-the-end iterator of the previous inner range.
  • Repeats the operations above until the inner iterator does not refer to the beginning of any range.
Finally, decrements the inner iterator as if by std::visit ( [ ] ( auto & it) { --it; } inner_it_ );
5) Equivalent to auto tmp = *this;
--*this;
return tmp;

Return value

1,4) *this
3,5) A copy of *this that was made before the change.
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