std::indirect_equivalence_relation

 

C++

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功能特性测试宏 (C++20)

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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) basic_const_iterator (C++23) const_iterator (C++23) const_sentinel (C++23) 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) make_const_iterator (C++23) make_const_sentinel (C++23) 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)

 

在标头 <iterator> 定义
template<class F, class I1, class I2 = I1> concept indirect_equivalence_relation =   std::indirectly_readable<I1> &&   std::indirectly_readable<I2> &&   std::copy_constructible<F> &&   std::equivalence_relation<F&, std::iter_value_t<I1>&, std::iter_value_t<I2>&> &&   std::equivalence_relation<F&, std::iter_value_t<I1>&, std::iter_reference_t<I2>> &&   std::equivalence_relation<F&, std::iter_reference_t<I1>, std::iter_value_t<I2>&> &&   std::equivalence_relation<F&, std::iter_reference_t<I1>, std::iter_reference_t<I2>> &&   std::equivalence_relation<F&, std::iter_common_reference_t<I1>, std::iter_common_reference_t<I2>>;		(C++20 起)

概念 indirect_equivalence_relation 指定调用作为其参数的等价关系的算法的要求。此概念与 std::equivalence_relation 间的关键区别是它被应用到 I1 与 I2 所引用的类型，而非 I1 与 I2 自身。

语义要求

F 、 I1 与 I2 实现 indirect_equivalence_relation 仅若其所蕴含的概念均得以实现。