std::ostream_iterator<T,CharT,Traits>::ostream_iterator

 

C++

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自立与有宿主实现

具名要求

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概念库 (C++20)

诊断库

工具库

字符串库

容器库

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范围库 (C++20)

算法库

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本地化库

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文件系统库 (C++17)

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原子操作库 (C++11)

线程支持库 (C++11)

技术规范

 

迭代器库

迭代器概念
indirectly_readable (C++20) indirectly_writable (C++20) weakly_incrementable (C++20) incrementable (C++20) input_or_output_iterator (C++20) sentinel_for (C++20) sized_sentinel_for (C++20)	input_iterator (C++20) output_iterator (C++20) forward_iterator (C++20) bidirectional_iterator (C++20) random_access_iterator (C++20) contiguous_iterator (C++20)
迭代器原语
iterator_traits input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag (C++20) iterator (C++17 中弃用)	incrementable_traits (C++20) indirectly_readable_traits (C++20) iter_value_titer_difference_titer_reference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++20)(C++20)(C++20)
算法概念与工具
间接可调用概念
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)
常用算法要求
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)
工具
indirect_result_t	projected
迭代器适配器
reverse_iterator move_iterator (C++11) move_sentinel (C++20) common_iterator (C++20) counted_iterator (C++20) back_insert_iterator front_insert_iterator insert_iterator	make_reverse_iterator (C++14) make_move_iterator (C++11) default_sentinel_tdefault_sentinel (C++20)(C++20) unreachable_sentinel_tunreachable_sentinel (C++20)(C++20) back_inserter front_inserter inserter
流迭代器
istream_iterator ostream_iterator	istreambuf_iterator ostreambuf_iterator
迭代器定制点
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) endcend (C++11)(C++14) sizessize (C++17)(C++20)	rbegincrbegin (C++14)(C++14) rendcrend (C++14)(C++14) empty (C++17) data (C++17)

 

std::ostream_iterator

成员函数

ostream_iterator::ostream_iterator

ostream_iterator::~ostream_iterator

ostream_iterator::operator=

ostream_iterator::operator*

ostream_iterator::operator++ostream_iterator::operator++(int)

 

ostream_iterator( ostream_type& stream, const CharT* delim );	(1)
ostream_iterator( ostream_type& stream );	(2)

1) 以 stream 为关联流并以 delim 为分隔符构造迭代器。

2) 以 stream 为关联流并以空指针为分隔符构造迭代器。

参数

stream	-	此迭代器所访问的输出流
delim	-	在每次输出后插入流的空终止字符串

示例

运行此代码

#include <iostream>
#include <iterator>
#include <algorithm>
#include <numeric>
int main()
{
    std::ostream_iterator<char> oo {std::cout};
    std::ostream_iterator<int> i1 {std::cout, ", "};
    std::fill_n(i1, 5, -1);
    *oo++ = '\n';
 
    std::ostream_iterator<double> i2 {std::cout, "; "};
    *i2++ = 3.14;
    *i2++ = 2.71;
    *oo++ = '\n';
 
    std::common_iterator<std::counted_iterator<std::ostream_iterator<float>>,
                         std::default_sentinel_t>
        first { std::counted_iterator{std::ostream_iterator<float>{std::cout," ~ "}, 5} },
        last { std::default_sentinel };
    std::iota(first, last, 2.2);
    *oo++ = '\n';
}

输出：

-1, -1, -1, -1, -1,
3.14; 2.71;
2.2 ~ 3.2 ~ 4.2 ~ 5.2 ~ 6.2 ~

缺陷报告

下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。

DR	应用于	出版时的行为	正确行为
P2325R3	C++20	由于 C++20 迭代器必须为 default_initializable 提供了默认构造函数	与该要求一同移除