std::ostreambuf_iterator<CharT,Traits>::ostreambuf_iterator

 

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迭代器库

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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)
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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)
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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	projected
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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
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ranges::iter_move (C++20)
ranges::iter_swap (C++20)
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advance distance prev (C++11) next (C++11)	ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)
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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::ostreambuf_iterator

成员函数

ostreambuf_iterator::ostreambuf_iterator

ostreambuf_iterator::operator=

ostreambuf_iterator::operator*

ostreambuf_iterator::operator++ostreambuf_iterator::operator++(int)

ostreambuf_iterator::failed

 

	(1)
ostreambuf_iterator( streambuf_type* buffer ) throw();			(C++11 前)
ostreambuf_iterator( streambuf_type* buffer ) noexcept;			(C++11 起)
		(2)
ostreambuf_iterator( ostream_type& stream ) throw();				(C++11 前)
ostreambuf_iterator( ostream_type& stream ) noexcept;				(C++11 起)

1) 构造迭代器，将私有的 streambuf_type* 成员设为 buffer 并将 failed() 标志设为 false 。若 buffer 是空指针则行为未定义。

2) 同 ostreambuf_iterator(stream.rdbuf()) 。

参数

stream	-	将关联其 rdbuf() 到此迭代器的输出流
buffer	-	此迭代器要访问的输出流缓冲

示例

运行此代码

#include <iostream>
#include <fstream>
#include <iterator>
int main()
{
    std::basic_filebuf<char> f;
    f.open("test.txt", std::ios::out);
 
    std::ostreambuf_iterator<char> out1(&f);
 
    std::ostreambuf_iterator<wchar_t> out2(std::wcout);
 
    *out1 = 'a';
    *out2 = L'a';
}

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