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

 

C++

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技術規範

符號索引

外部庫

 

範圍庫 (Ranges library)

範圍訪問 begin cbegin   end cend rbegin crbegin   rend crend size ssize   data cdata reserve_hint (C++26)   empty

範圍轉換 (Range conversions) std::from_range_t std::from_range (C++23)(C++23)     to (C++23)

懸空迭代器處理 (Dangling iterator handling) dangling borrowed_iterator_t borrowed_subrange_t

範圍原語 (Range primitives)
range_size_trange_difference_trange_value_t elements_of (C++23)	iterator_tconst_iterator_tsentinel_tconst_sentinel_t (C++23)(C++23)	range_reference_trange_const_reference_trange_rvalue_reference_trange_common_reference_t (C++23)

範圍概念 (Range concepts)
range borrowed_range    common_range	sized_range viewable_range    view	input_range output_range forward_range	bidirectional_range    random_access_range contiguous_range	approximately_sized_range (C++26) constant_range (C++23)

檢視
view_interface	subrange

範圍工廠 (Range factories)
empty_viewviews::empty	single_viewviews::single	basic_istream_viewviews::istream	iota_viewviews::iota	repeat_viewviews::repeat (C++23)(C++23)

範圍介面卡 (Range adaptors)
views::all_tviews::all as_rvalue_viewviews::as_rvalue (C++23)(C++23)   filter_viewviews::filter transform_viewviews::transform take_viewviews::take take_while_viewviews::take_while common_viewviews::common views::counted to_input_viewviews::to_input (C++26)(C++26)	ref_view drop_viewviews::drop drop_while_viewviews::drop_while lazy_split_viewviews::lazy_split split_viewviews::split join_viewviews::join join_with_viewviews::join_with (C++23)(C++23)   concat_viewviews::concat (C++26)(C++26) cache_latest_viewviews::cache_latest (C++26)(C++26)	owning_view reverse_viewviews::reverse as_const_viewviews::as_const (C++23)(C++23) elements_viewviews::elements keys_viewviews::keys values_viewviews::values enumerate_viewviews::enumerate (C++23)(C++23) zip_viewviews::zip (C++23)(C++23) zip_transform_viewviews::zip_transform (C++23)(C++23)	adjacent_viewviews::adjacent (C++23)(C++23) views::pairwise (C++23) adjacent_transform_viewviews::adjacent_transform (C++23)(C++23) views::pairwise_transform (C++23) chunk_viewviews::chunk (C++23)(C++23) slide_viewviews::slide (C++23)(C++23) chunk_by_viewviews::chunk_by (C++23)(C++23) stride_viewviews::stride (C++23)(C++23) cartesian_product_viewviews::cartesian_product (C++23)(C++23)

範圍生成器 (Range generators) std::generator (C++23)

範圍介面卡閉包物件 (Range adaptor closure objects) range_adaptor_closure (C++23)

範圍介面卡物件 (Range adaptor objects)

輔助項 (Helper items)
copyable-box movable-box (直到 C++23)  (C++23)	simple-view non-propagating-cache

 

std::ranges::join_view

成員函式

join_view::join_view

join_view::base

join_view::begin

join_view::end

推導指引

迭代器 (Iterator)

join_view::iterator::iterator

join_view::iterator::operator* join_view::iterator::operator->

join_view::iterator::operator++ join_view::iterator::operator++(int) join_view::iterator::operator-- join_view::iterator::operator--(int)

join_view::iterator::satisfy

operator==(join_view::iterator)

iter_move(join_view::iterator)

iter_swap(join_view::iterator)

哨兵 (Sentinel)

join_view::sentinel::sentinel

operator==(join_view::iterator,join_view::sentinel)

 

constexpr /*迭代器*/& operator++();	(1)	(C++20 起)
constexpr void operator++( int );	(2)	(C++20 起)
constexpr /*iterator*/ operator++( int )     requires /*ref-is-glvalue*/ && ranges::forward_range<Base> &&              ranges::forward_range<ranges::range_reference_t<Base>>;	(3)	(C++20 起)
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)	(C++20 起)
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)	(C++20 起)

遞增或遞減底層迭代器。

令 inner_ 和 outer_ 為底層迭代器，parent_ 為指向父 ranges::join_view 的指標，常量 /*ref-is-glvalue*/ 為 std::is_reference_v<ranges::range_reference_t<Base>>。

1) 令 /*inner-range*/ 為

• *outer_，若 /*ref-is-glvalue*/ == true；
• *parent_->inner_ 否則。

等價於

auto&& inner_rng = /*inner-range*/;
if (++inner_ == ranges::end(inner_rng))
{
    ++outer_;
    satisfy();
}
return *this;

2) 等價於：++*this。

3) 等效於

auto tmp = *this;
++*this;
return tmp;

4) 等價於

if (outer_ == ranges::end(parent_->base_))
    inner_ = ranges::end(*--outer_);
while (inner_ == ranges::begin(*outer_))
    inner_ = ranges::end(*--outer_);
--inner_;
return *this;

5) 等同於

auto tmp = *this;
--*this;
return tmp;

引數

(無)

返回值

1,4) *this

2) (無)

3,5) 更改前 *this 的副本。