std::counted_iterator<I>::运算符*,->

 

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indirectly_readable (C++20) indirectly_writable (C++20) weakly_incrementable (C++20) incrementable (C++20) is-integer-like is-signed-integer-like (C++20)(C++20)	sentinel_for (C++20) sized_sentinel_for (C++20) input_iterator (C++20) output_iterator (C++20) input_or_output_iterator (C++20)	forward_iterator (C++20) bidirectional_iterator (C++20) random_access_iterator (C++20) contiguous_iterator (C++20)
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input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag (C++20)	iter_value_titer_difference_titer_reference_titer_const_reference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++20)(C++23)(C++20)(C++20)	迭代器 (在 C++17 中已弃用) iterator_traits incrementable_traits (C++20) indirectly_readable_traits (C++20)
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indirectly_unary_invocableindirectly_regular_unary_invocable (C++20)(C++20)	indirect_unary_predicate (C++20) indirect_binary_predicate (C++20)	indirect_equivalence_relation (C++20) indirect_strict_weak_order (C++20)
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indirectly_movable (C++20) indirectly_movable_storable (C++20) indirectly_copyable (C++20)	indirectly_copyable_storable (C++20)   indirectly_swappable (C++20) indirectly_comparable (C++20)	permutable (C++20) mergeable (C++20) sortable (C++20)
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indirect_result_t (C++20)	projected (C++20)	projected_value_t (C++26)
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reverse_iterator make_reverse_iterator (C++14) move_iterator (C++11) make_move_iterator (C++11) default_sentinel_tdefault_sentinel (C++20)(C++20) unreachable_sentinel_tunreachable_sentinel (C++20)(C++20)	front_insert_iterator back_insert_iterator inserter insert_iterator front_inserter back_inserter move_sentinel (C++20)	common_iterator (C++20) counted_iterator (C++20) basic_const_iterator (C++23) const_iterator (C++23) const_sentinel (C++23) make_const_iterator (C++23) make_const_sentinel (C++23)
流迭代器 istream_iterator    ostream_iterator istreambuf_iterator ostreambuf_iterator	迭代器自定义点 ranges::iter_move (C++20) ranges::iter_swap (C++20)
迭代器操作 advance distance prev (C++11)   next (C++11) ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)	范围访问 begincbegin (C++11)(C++14) rbegincrbegin (C++14)(C++14)   endcend (C++11)(C++14) rendcrend (C++14)(C++14)   sizessize (C++17)(C++20) empty (C++17) data (C++17)

 

std::counted_iterator

成员函数

counted_iterator::counted_iterator

counted_iterator::operator=

counted_iterator::base

counted_iterator::count

counted_iterator::运算符*counted_iterator::运算符->

counted_iterator::operator[]

counted_iterator::运算符++counted_iterator::运算符++(int)counted_iterator::运算符+counted_iterator::运算符+=counted_iterator::运算符--counted_iterator::运算符--(int)counted_iterator::运算符-counted_iterator::运算符-=

非成员函数

运算符==运算符<=> (C++20)(C++20)

运算符==(default_sentinel_t) (C++20)

运算符+ (C++20)

运算符- (C++20)

运算符-(default_sentinel_t) (C++20)

iter_move (C++20)

iter_swap (C++20)

辅助类

iterator_traits<std::counted_iterator> (C++20)

 

constexpr decltype(auto) 运算符*();	(1)	(自 C++20 起)
constexpr decltype(auto) 运算符*() const     requires /*可解引用*/<const I>;	(2)	(自 C++20 起)
constexpr auto 运算符->() const noexcept     requires std::contiguous_iterator<I>;	(3)	(自 C++20 起)

1,2) 返回到当前元素的引用。如果 this->count() <= 0，则行为未定义。该函数体等效于 return *current;。

3) 返回指向当前元素的指针。该函数体等效于 return std::to_address(current);。

参数

(无)

返回值

到当前元素的引用或指针。

示例

运行此代码

#include <complex>
#include <iostream>
#include <iterator>
using std::operator""i;
 
int main()
{
    const auto il = {1.i, 2.i, 3.i, 4.i, 5.i};
 
    for (std::counted_iterator i{il.begin() + 1, 3}; i != std::default_sentinel; ++i)
        std::cout << *i << ' ';
    std::cout << '\n';
 
    for (std::counted_iterator i{il.begin() + 1, 3}; i != std::default_sentinel; ++i)
        std::cout << i->imag() << ' ';
    std::cout << '\n';
}

输出

(0,2) (0,3) (0,4)
2 3 4

参见

operator[]

通过索引访问元素 (公共成员函数)