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

From cppreference.com
< cpp‎ | ranges‎ | join view‎ | iterator
 
 
Ranges library
Range adaptors
 
 
constexpr /*iterator*/& operator++();
(1) (since C++20)
constexpr void operator++( int );
(2) (since C++20)
constexpr /*iterator*/ operator++( int )

    requires /*ref-is-glvalue*/ && ranges::forward_range<Base> &&

             ranges::forward_range<ranges::range_reference_t<Base>>;
(3) (since C++20)
constexpr iterator& operator--()

    requires /*ref-is-glvalue*/ && ranges::bidirectional_range<Base> &&
             ranges::bidirectional_range<ranges::range_reference_t<Base>> &&

             ranges::common_range<ranges::range_reference_t<Base>>;
(4) (since C++20)
constexpr /*iterator*/ operator--( int )

    requires /*ref-is-glvalue*/ && ranges::bidirectional_range<Base> &&
             ranges::bidirectional_range<ranges::range_reference_t<Base>> &&

             ranges::common_range<ranges::range_reference_t<Base>>;
(5) (since C++20)

Increments or decrements the underlying iterator.

Let inner_ and outer_ be the underlying iterators, and parent_ be the pointer to parent ranges::join_view, the constant /*ref-is-glvalue*/ be std::is_reference_v<ranges::range_reference_t<Base>>.

1) Let /*inner-range*/ be:
  • *outer_, if /*ref-is-glvalue*/ == true;
  • *parent_->inner_ otherwise.

Equivalent to:

auto&& inner_rng = /*inner-range*/;
if (++inner_ == ranges::end(inner_rng))
{
    ++outer_;
    satisfy();
}
return *this;
2) Equivalent to: ++*this.
3) Equivalent to:
auto tmp = *this;
++*this;
return tmp;
4) Equivalent to:
if (outer_ == ranges::end(parent_->base_))
    inner_ = ranges::end(*--outer_);
while (inner_ == ranges::begin(*outer_))
    inner_ = ranges::end(*--outer_);
--inner_;
return *this;
5) Equivalent to:
auto tmp = *this;
--*this;
return tmp;

[edit] Parameters

(none)

[edit] Return value

1,4) *this
2) (none)
3,5) a copy of *this that was made before the change.