はじめに(Introduction)
N4910 Working Draft, Standard for Programming Language C++
n4910は、ISO/IEC JTC1 SC22 WG21の作業原案(Working Draft)です。
公式のISO/IEC 14882原本ではありません。
ISO/IEC JTC1 SC22 WG21では、可能な限り作業文書を公開し、幅広い意見を求めています。
一連の記事はコード断片をコンパイルできる形にする方法を検討してコンパイル、リンク、実行して、規格案の原文と処理系(g++, Clang++)との違いを確認し、技術内容を検討し、ISO/IEC JTC1 SC22 WG21にフィードバックするために用います。
また、CERT C++, MISRA C++等のコーディング標準のコード断片をコンパイルする際の参考にさせていただこうと考えています。CERT C++, MISRA C++が標準化の動きとの時間的なずれがあれば確認できれば幸いです。また、boostライブラリとの関連、Linux OS, TOPPERSカーネル、g++(GCC), clang++(LLVM）との関係も調査中です。
何か、抜け漏れ、耳より情報がありましたらおしらせくださると幸いです。
<この項は書きかけです。順次追記します。>
背景(back ground)
C/C++でコンパイルエラーが出ると、途方にくれることがしばしばあります。
何回かに１回は、該当するエラーが検索できます。
ただ、条件が違っていて、そこでの修正方法では目的を達成しないこともしばしばです。いろいろな条件のコンパイルエラーとその対応方法について、広く記録することによって、いつか同じエラーに遭遇した時にやくに立つことを目指しています。
この半年の間で、三度、自分のネットでの記録に助けられたことがあります。
また過去に解決できなかった記録を１０種類以上、最近になって解決できたことがあります。それは、主に次の３つの情報に基づいています。
cpprefjp - C++日本語リファレンス
コンパイラの実装状況
また
https://researchmap.jp/joub9b3my-1797580/#_1797580
に記載したサイトのお世話になっています。
作業方針(sequence)
Clang++では-std=c++03, C++2bの2種類
g++では-std=c++03, c++2bの２種類
でコンパイルし、
１）コンパイルエラーを収集する。
２）コンパイルエラーをなくす方法を検討する。
コンパイルエラーになる例を示すだけが目的のコードは、コンパイルエラーをなくすのではなく、コンパイルエラーの種類を収集するだけにする。
文法を示すのが目的のコード場合に、コンパイルエラーをなくすのに手間がかかる場合は、順次作業します。
３）リンクエラーをなくす方法を検討する。
文法を示すのが目的のコード場合に、リンクエラーをなくすのに手間がかかる場合は、順次作業します。
４）意味のある出力を作る。
コンパイル、リンクが通っても、意味のある出力を示そうとすると、コンパイル・リンクエラーが出て収拾できそうにない場合がある。順次作業します。
１）だけのものから４）まで進んだものと色々ある状態です。一歩でも前に進むご助言をお待ちしています。「検討事項」の欄に現状を記録するようにしています。
C++N4910:2022 Standard Working Draft on ISO/IEC 14882(0) sample code compile list
C++N4741, 2018 Standard Working Draft on ISO/IEC 14882 sample code compile list
C++N4606, 2016符号断片編纂一覧(example code compile list)
C++N4606, 2016 Working Draft 2016, ISO/IEC 14882, C++ standard(1) Example code compile list
https://qiita.com/kaizen_nagoya/items/df5d62c35bd6ed1c3d43/
C++N3242, 2011 sample code compile list on clang++ and g++
編纂器(Compiler)
clang++ --version
Debian clang version 14.0.5-++20220610033153+c12386ae247c-1~exp1~20220610153237.151
Target: x86_64-pc-linux-gnu, Thread model: posix, InstalledDir: /usr/bin
g++- --version
g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
27.6 Non-modifying sequence operations [alg.nonmodifying] C++N4910:2022 (660) p1193.cpp
算譜(source code)
p1193.cpp
// C++N4910 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/n4910.pdf
const char * n4910 = "27.6 Non-modifying sequence operations [alg.nonmodifying] C++N4910:2022 (660) p1193.cpp";
// Debian clang version 14.0.5-++20220610033153+c12386ae247c-
// g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc.
// Edited by Dr. OGAWA Kiyoshi. Compile procedure and results record.
// C++N4910:2022 Standard Working Draft on ISO/IEC 14882(0) sample code compile list
// https://qiita.com/kaizen_nagoya/items/fc957ddddd402004bb91
#include "N4910.h"
using namespace std;
// 27.6.1 All of [alg.all.of]
template<class InputIterator, class Predicate>
constexpr bool all_of(InputIterator first, InputIterator last, Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
bool all_of(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
Predicate pred);
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr bool ranges::all_of(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr bool ranges::all_of(R&& r, Pred pred, Proj proj = {});
Let E be:
— pred(*i) for the overloads in namespace std;
— invoke(pred, invoke(proj, *i)) for the overloads in namespace ranges.
Returns: false if E is false for some iterator i in the range [first, last), and true otherwise. Complexity: At most last - first applications of the predicate and any projection.
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr bool ranges::any_of(R&& r, Pred pred, Proj proj = {});
// Let E be: — pred(*i) for the overloads in namespace std;
// — invoke(pred, invoke(proj, *i)) for the overloads in namespace ranges.
} };
template<class O, class T>
struct out_value_result {
[[no_unique_address]] O out;
[[no_unique_address]] T value;
template<class O2, class T2>
requires convertible_to<const O&, O2> && convertible_to<const T&, T2>
constexpr operator out_value_result<O2, T2>() const & {
return {out, value};
}
template<class O2, class T2>
requires convertible_to<O, O2> && convertible_to<T, T2>
constexpr operator out_value_result<O2, T2>() && {
return {std::move(out), std::move(value)};
} };
}
// Non-modifying sequence operations All of
// [alg.nonmodifying] [alg.all.of] [alg.none.of]
template<class InputIterator, class Predicate>
constexpr bool all_of(InputIterator first, InputIterator last, Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
bool all_of(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
Predicate pred);
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr bool ranges::all_of(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
27.6.2 Any of [alg.any.of]
template<class InputIterator, class Predicate>
constexpr bool any_of(InputIterator first, InputIterator last, Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
bool any_of(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
Predicate pred);
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr bool ranges::any_of(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr bool ranges::none_of(R&& r, Pred pred, Proj proj = {});
// Let E be: — pred(*i) for the overloads in namespace std;
// — invoke(pred, invoke(proj, *i)) for the overloads in namespace ranges.
Returns: true if E is true for some iterator i in the range [first, last), and false otherwise. Complexity: At most last - first applications of the predicate and any projection.
template<class InputIterator, class Predicate>
constexpr bool none_of(InputIterator first, InputIterator last, Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
bool none_of(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
Predicate pred);
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr bool ranges::none_of(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
// Returns: false if E is true for some iterator i in the range [first, last), and true otherwise. Complexity: At most last - first applications of the predicate and any projection.
// 27.6.4 For each [alg.foreach]
template<class InputIterator, class Function>
constexpr Function for_each(InputIterator first, InputIterator last, Function f);
// Preconditions: Function meets the Cpp17MoveConstructible requirements (Table 30).
// [Note 1: Function need not meet the requirements of // Cpp17CopyConstructible (Table 31).
Effects: Applies f to the result of dereferencing every iterator in the range [first, last), starting from first and proceeding to last -
// [Note 2: If the type of first meets the requirements of a mutable iterator, f can apply non-constant functions through the dereferenced iterator.
// Returns: f.
// Complexity: Applies f exactly last - first times. Remarks: If f returns a result, the result is ignored.
template<class ExecutionPolicy, class ForwardIterator, class Function>
void for_each(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
Function f);
Preconditions: Function meets the Cpp17CopyConstructible requirements.
Effects: Applies f to the result of dereferencing every iterator in the range [first, last).
[Note 3: If the type of first meets the requirements of a mutable iterator, f can apply non-constant functions through the dereferenced iterator. —end note]
Complexity: Applies f exactly last - first times.
Remarks: If f returns a result, the result is ignored. Implementations do not have the freedom granted
under 27.3.3 to make arbitrary copies of elements from the input sequence.
[Note 4: Does not return a copy of its Function parameter, since parallelization often does not permit efficient
state accumulation. —end note]
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirectly_unary_invocable<projected<I, Proj>> Fun>
constexpr ranges::for_each_result<I, Fun>
ranges::for_each(I first, S last, Fun f, Proj proj = {});
template<input_range R, class Proj = identity,
indirectly_unary_invocable<projected<iterator_t<R>, Proj>> Fun>
constexpr ranges::for_each_result<borrowed_iterator_t<R>, Fun>
ranges::for_each(R&& r, Fun f, Proj proj = {});
// Effects: Calls invoke(f, invoke(proj, *i)) for every iterator i in the range [first, last), starting from first and proceeding to last - 1.
// [Note 5 : If the result of invoke(proj, *i) is a mutable reference, f can apply non-constant functions.
// Returns: {last, std::move(f)}.
// Complexity: Applies f and proj exactly last - first times.
// Remarks: If f returns a result, the result is ignored.
// [Note 6: The overloads in namespace ranges require Fun to model copy_constructible.
template<class InputIterator, class Size, class Function>
constexpr InputIterator for_each_n(InputIterator first, Size n, Function f);
Mandates: The type Size is convertible to an integral type (7.3.9, 11.4.8).
// Preconditions: n >= 0 is true. Function meets the Cpp17MoveConstructible requirements.
// [Note 7: Function need not meet the requirements of Cpp17CopyConstructible.
// Effects: Applies f to the result of dereferencing every iterator in the range [first, first + n) in order.
// [Note 8: If the type of first meets the requirements of a mutable iterator, f can apply non-constant functions through the dereferenced iterator.
// Returns: first + n.
// Remarks: If f returns a result, the result is ignored.
template<class ExecutionPolicy, class ForwardIterator, class Size, class Function>
ForwardIterator for_each_n(ExecutionPolicy&& exec, ForwardIterator first, Size n,
Function f);
// Mandates: The type Size is convertible to an integral type (7.3.9, 11.4.8).
// Preconditions: n >= 0 is true. Function meets the Cpp17CopyConstructible requirements.
// Effects: Applies f to the result of dereferencing every iterator in the range [first, first + n).
[Note 9: If the type of first meets the requirements of a mutable iterator, f can apply non-constant functions through the dereferenced iterator. —end note]
Returns: first + n.
Remarks: If f returns a result, the result is ignored. Implementations do not have the freedom granted
under 27.3.3 to make arbitrary copies of elements from the input sequence.
template<input_iterator I, class Proj = identity,
indirectly_unary_invocable<projected<I, Proj>> Fun>
constexpr ranges::for_each_n_result<I, Fun>
ranges::for_each_n(I first, iter_difference_t<I> n, Fun f, Proj proj = {});
// Preconditions: n >= 0 is true.
// Effects: Calls invoke(f, invoke(proj, *i)) for every iterator i in the range [first, first + n) in
order.
// [Note 10 : If the result of invoke(proj, *i) is a mutable reference, f can apply non-constant functions.
// Returns: {first + n, std::move(f)}.
// Remarks: If f returns a result, the result is ignored.
// [Note 11: The overload in namespace ranges requires Fun to model copy_constructible.
// 27.6.5 Find [alg.find]
template<class InputIterator, class T>
constexpr InputIterator find(InputIterator first, InputIterator last,
const T& value);
template<class ExecutionPolicy, class ForwardIterator, class T>
ForwardIterator find(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
const T& value);
template<class InputIterator, class Predicate>
constexpr InputIterator find_if(InputIterator first, InputIterator last,
Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
ForwardIterator find_if(ExecutionPolicy&& exec, ForwardIterator first, ForwardIterator last,
Predicate pred);
template<class InputIterator, class Predicate>
constexpr InputIterator find_if_not(InputIterator first, InputIterator last,
Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
ForwardIterator find_if_not(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
Predicate pred);
template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
constexpr I ranges::find(I first, S last, const T& value, Proj proj = {});
template<input_range R, class T, class Proj = identity>
requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
constexpr borrowed_iterator_t<R>
ranges::find(R&& r, const T& value, Proj proj = {});
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr I ranges::find_if(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr borrowed_iterator_t<R>
ranges::find_if(R&& r, Pred pred, Proj proj = {});
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr I ranges::find_if_not(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr borrowed_iterator_t<R>
ranges::find_if_not(R&& r, Pred pred, Proj proj = {});
// Let E be: — *i == value for find;
// — pred(*i) != false for find_if;
// — pred(*i) == false for find_if_not;
// — bool(invoke(proj, *i) == value) for ranges::find;
// — bool(invoke(pred, invoke(proj, *i))) for ranges::find_if;
// — bool(!invoke(pred, invoke(proj, *i))) for ranges::find_if_not.
// Returns: The first iterator i in the range [first, last) for which E is true. Returns last if no such iterator is found.
// Complexity: At most last - first applications of the corresponding predicate and any projection. 27.6.6 Find end [alg.find.end]
template<class ForwardIterator1, class ForwardIterator2>
constexpr ForwardIterator1
find_end(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr borrowed_subrange_t<R1>
ranges::find_end(R1&& r1, R2&& r2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
// Let: — pred be equal_to{} for the overloads with no parameter pred;
// — E be:
// — pred(*(i + n), *(first2 + n)) for the overloads in namespace std;
// — invoke(pred, invoke(proj1, *(i + n)), invoke(proj2, *(first2 + n))) for the over-loads in namespace ranges;
// — i be last1 if [first2,last2) is empty, or if (last2 - first2) > (last1 - first1) is true, or if there is no iterator in the range [first1, last1 - (last2 - first2)) such that for every non-negative integer n < (last2 - first2), E is true. Otherwise i is the last such iterator in [first1,last1 - (last2 - first2)).
// Returns: — i for the overloads in namespace std.
// — {i, i + (i == last1 ? 0 : last2 - first2)} for the overloads in namespace ranges.
// Complexity: At most (last2 - first2) * (last1 - first1 - (last2 - first2) + 1) applica- tions of the corresponding predicate and any projections.
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
ForwardIterator1
find_end(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
constexpr ForwardIterator1
find_end(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
ForwardIterator1
find_end(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr subrange<I1>
ranges::find_end(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<forward_range R1, forward_range R2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
// 27.6.7 Find first [alg.find.first.of]
template<class InputIterator, class ForwardIterator>
constexpr InputIterator
find_first_of(InputIterator first1, InputIterator last1,
ForwardIterator first2, ForwardIterator last2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
ForwardIterator1
find_first_of(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class InputIterator, class ForwardIterator,
class BinaryPredicate>
constexpr InputIterator
find_first_of(InputIterator first1, InputIterator last1,
ForwardIterator first2, ForwardIterator last2,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
ForwardIterator1
find_first_of(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
template<input_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr I1 ranges::find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<input_range R1, forward_range R2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr borrowed_iterator_t<R1>
ranges::find_first_of(R1&& r1, R2&& r2,
Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
// Let E be: — *i == *j for the overloads with no parameter pred;
// — pred(*i, *j) != false for the overloads with a parameter pred and no parameter proj1;
// — bool(invoke(pred, invoke(proj1, *i), invoke(proj2, *j))) for the overloads with param- eters pred and proj1.
// Effects: Finds an element that matches one of a set of values.
// Returns: The first iterator i in the range [first1, last1) such that for some iterator j in the range
[first2, last2) E holds. Returns last1 if [first2, last2) is empty or if no such iterator is found. Complexity: At most (last1-first1) * (last2-first2) applications of the corresponding predicate
and any projections.
// 27.6.8 Adjacent find [alg.adjacent.find]
template<class ForwardIterator>
constexpr ForwardIterator
adjacent_find(ForwardIterator first, ForwardIterator last);
template<class ExecutionPolicy, class ForwardIterator>
ForwardIterator
adjacent_find(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last);
template<class ForwardIterator, class BinaryPredicate>
constexpr ForwardIterator
adjacent_find(ForwardIterator first, ForwardIterator last,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator, class BinaryPredicate>
ForwardIterator
adjacent_find(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
BinaryPredicate pred);
projected<iterator_t<R>, Proj>> Pred = ranges::equal_to>
constexpr borrowed_iterator_t<R> ranges::adjacent_find(R&& r, Pred pred = {}, Proj proj = {});
Let E be:
— *i == *(i + 1) for the overloads with no parameter pred;
— pred(*i, *(i + 1)) != false for the overloads with a parameter pred and no parameter proj;
— bool(invoke(pred, invoke(proj, *i), invoke(proj, *(i + 1)))) for the overloads with both parameters pred and proj.
Returns: The first iterator i such that both i and i + 1 are in the range [first, last) for which E holds. Returns last if no such iterator is found.
// Complexity: For the overloads with no ExecutionPolicy, exactly
min((i - first) + 1, (last - first) - 1) applications of the corresponding predicate, where i is adjacent_find’s return value. For the overloads with an ExecutionPolicy, O(last - first) applications of the corresponding predicate, and no more than twice as many applications of any projection.
indirect_unary_predicate<projected<iterator_t<R>, Proj>> Pred>
constexpr range_difference_t<R>
ranges::count_if(R&& r, Pred pred, Proj proj = {});
// Let E be: — *i == value for the overloads with no parameter pred or proj;
// — pred(*i) != false for the overloads with a parameter pred but no parameter proj;
template<forward_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_binary_predicate<projected<I, Proj>,
projected<I, Proj>> Pred = ranges::equal_to>
constexpr I ranges::adjacent_find(I first, S last, Pred pred = {}, Proj proj = {});
template<forward_range R, class Proj = identity,
indirect_binary_predicate<projected<iterator_t<R>, Proj>,
// 27.6.9 Count
template<class InputIterator, class T>
constexpr typename iterator_traits<InputIterator>::difference_type
count(InputIterator first, InputIterator last, const T& value);
template<class ExecutionPolicy, class ForwardIterator, class T>
typename iterator_traits<ForwardIterator>::difference_type
count(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last, const T& value);
template<class InputIterator, class Predicate>
constexpr typename iterator_traits<InputIterator>::difference_type
count_if(InputIterator first, InputIterator last, Predicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Predicate>
typename iterator_traits<ForwardIterator>::difference_type
count_if(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last, Predicate pred);
template<input_iterator I, sentinel_for<I> S, class T, class Proj = identity>
requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*>
constexpr iter_difference_t<I>
ranges::count(I first, S last, const T& value, Proj proj = {});
template<input_range R, class T, class Proj = identity>
[alg.count]
requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
constexpr range_difference_t<R>
ranges::count(R&& r, const T& value, Proj proj = {});
template<input_iterator I, sentinel_for<I> S, class Proj = identity,
indirect_unary_predicate<projected<I, Proj>> Pred>
constexpr iter_difference_t<I>
ranges::count_if(I first, S last, Pred pred, Proj proj = {});
template<input_range R, class Proj = identity,
// — invoke(proj, *i) == value for the overloads with a parameter proj but no parameter pred; — bool(invoke(pred, invoke(proj, *i))) for the overloads with both parameters proj and pred.
// Effects: Returns the number of iterators i in the range [first, last) for which E holds. Complexity: Exactly last - first applications of the corresponding predicate and any projection.
// 27.6.10 Mismatch
template<class InputIterator1, class InputIterator2>
constexpr pair<InputIterator1, InputIterator2>
mismatch(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
pair<ForwardIterator1, ForwardIterator2>
mismatch(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2);
template<class InputIterator1, class InputIterator2,
class BinaryPredicate>
constexpr pair<InputIterator1, InputIterator2>
mismatch(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
pair<ForwardIterator1, ForwardIterator2>
mismatch(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, BinaryPredicate pred);
template<class InputIterator1, class InputIterator2>
constexpr pair<InputIterator1, InputIterator2>
mismatch(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, InputIterator2 last2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
pair<ForwardIterator1, ForwardIterator2>
mismatch(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class InputIterator1, class InputIterator2,
class BinaryPredicate>
constexpr pair<InputIterator1, InputIterator2>
mismatch(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, InputIterator2 last2,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
pair<ForwardIterator1, ForwardIterator2>
mismatch(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr ranges::mismatch_result<I1, I2>
ranges::mismatch(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
// [mismatch]
template<input_range R1, input_range R2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr ranges::mismatch_result<borrowed_iterator_t<R1>, borrowed_iterator_t<R2>>
ranges::mismatch(R1&& r1, R2&& r2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
Let last2 be first2 + (last1 - first1) for the overloads with no parameter last2 or r2. Let E be:
— !(*(first1 + n) == *(first2 + n)) for the overloads with no parameter pred;
— pred(*(first1 + n), *(first2 + n)) == false for the overloads with a parameter pred and
no parameter proj1;
— !invoke(pred, invoke(proj1, *(first1 + n)), invoke(proj2, *(first2 + n))) for the
overloads with both parameters pred and proj1. Let N be min(last1 - first1, last2 - first2).
Returns: { first1 + n, first2 + n }, where n is the smallest integer in [0,N) such that E holds, or N if no such integer exists.
© ISO/IEC
N4910
Complexity: At most N applications of the corresponding predicate and any projections.
27.6.11 Equal [alg.equal]
template<class InputIterator1, class InputIterator2>
constexpr bool equal(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
bool equal(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2);
template<class InputIterator1, class InputIterator2,
class BinaryPredicate>
constexpr bool equal(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
bool equal(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, BinaryPredicate pred);
template<class InputIterator1, class InputIterator2>
constexpr bool equal(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, InputIterator2 last2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
bool equal(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class InputIterator1, class InputIterator2,
class BinaryPredicate>
constexpr bool equal(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2, InputIterator2 last2,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
bool equal(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
§ 27.6.11
1200
1 (1.1) (1.2) (1.3) (1.3.1) (1.3.2)
2
3 (3.1)
(3.2)
(3.3)
(3.4)
(3.5)
class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr bool ranges::equal(R1&& r1, R2&& r2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
Let:
— last2 be first2 + (last1 - first1) for the overloads with no parameter last2 or r2;
— pred be equal_to{} for the overloads with no parameter pred;
— E be:
— pred(*i, *(first2 + (i - first1))) for the overloads with no parameter proj1;
— invoke(pred, invoke(proj1, *i), invoke(proj2, *(first2 + (i - first1)))) for
the overloads with parameter proj1.
Returns: If last1 - first1 != last2 - first2, return false. Otherwise return true if E holds
for every iterator i in the range [first1, last1) Otherwise, returns false. Complexity: If
— the types of first1, last1, first2, and last2 meet the Cpp17RandomAccessIterator require- ments (25.3.5.7) and last1 - first1 != last2 - first2 for the overloads in namespace std;
— the types of first1, last1, first2, and last2 pairwise model sized_sentinel_for (25.3.4.8) and last1 - first1 != last2 - first2 for the first overload in namespace ranges,
— R1 and R2 each model sized_range and ranges::distance(r1) != ranges::distance(r2) for the second overload in namespace ranges,
then no applications of the corresponding predicate and each projection; otherwise,
1
2 3
constexpr bool is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
Let last2 be first2 + (last1 - first1) for the overloads with no parameter named last2, and let pred be equal_to{} for the overloads with no parameter pred.
Mandates: ForwardIterator1 and ForwardIterator2 have the same value type. Preconditions: The comparison function is an equivalence relation.
© ISO/IEC
N4910
template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr bool ranges::equal(I1 first1, S1 last1, I2 first2, S2 last2,
Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<input_range R1, input_range R2, class Pred = ranges::equal_to,
— —
27.6.12
For the overloads with no ExecutionPolicy, at most min(last1 - first1, last2 - first2) applications of the corresponding predicate and any projections.
For the overloads with an ExecutionPolicy, O(min(last1 - first1, last2 - first2)) appli- cations of the corresponding predicate.
Is permutation [alg.is.permutation]
template<class ForwardIterator1, class ForwardIterator2>
constexpr bool is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2);
template<class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
constexpr bool is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, BinaryPredicate pred);
template<class ForwardIterator1, class ForwardIterator2>
constexpr bool is_permutation(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
§ 27.6.12 1201
6
7 (7.1) (7.1.1) (7.1.2) (7.1.3) (7.2)
class Proj1 = identity, class Proj2 = identity,
indirect_equivalence_relation<projected<iterator_t<R1>, Proj1>,
projected<iterator_t<R2>, Proj2>> Pred = ranges::equal_to>
constexpr bool ranges::is_permutation(R1&& r1, R2&& r2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
Returns: If last1 - first1 != last2 - first2, return false. Otherwise return true if there exists a permutation of the elements in the range [first2, last2), bounded by [pfirst, plast), such that ranges::equal(first1, last1, pfirst, plast, pred, proj1, proj2) returns true; otherwise, returns false.
Complexity: No applications of the corresponding predicate and projections if: — for the first overload,
— S1 and I1 model sized_sentinel_for<S1, I1>,
— S2 and I2 model sized_sentinel_for<S2, I2>, and — last1 - first1 != last2 - first2;
— for the second overload, R1 and R2 each model sized_range, and ranges::distance(r1) != ranges::distance(r2).
Otherwise, exactly last1 - first1 applications of the corresponding predicate and projections if ranges::equal(first1, last1, first2, last2, pred, proj1, proj2) would return true; other- wise, at worst O(N2), where N has the value last1 - first1.
4
5
Returns: If last1 - first1 != last2 - first2, return false. Otherwise return true if there exists a permutation of the elements in the range [first2, last2), beginning with ForwardIterator2 begin, such that equal(first1, last1, begin, pred) returns true; otherwise, returns false.
Complexity: No applications of the corresponding predicate if ForwardIterator1 and ForwardIter- ator2 meet the requirements of random access iterators and last1 - first1 != last2 - first2. Otherwise, exactly last1 - first1 applications of the corresponding predicate if equal(first1, last1, first2, last2, pred) would return true; otherwise, at worst O(N2), where N has the value last1 - first1.
© ISO/IEC N4910
template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2,
sentinel_for<I2> S2, class Proj1 = identity, class Proj2 = identity,
indirect_equivalence_relation<projected<I1, Proj1>,
projected<I2, Proj2>> Pred = ranges::equal_to>
constexpr bool ranges::is_permutation(I1 first1, S1 last1, I2 first2, S2 last2,
Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<forward_range R1, forward_range R2,
27.6.13 Search [alg.search]
template<class ForwardIterator1, class ForwardIterator2>
constexpr ForwardIterator1
search(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
ForwardIterator1
search(ExecutionPolicy&& exec,
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2);
template<class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
constexpr ForwardIterator1
search(ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
class BinaryPredicate>
ForwardIterator1
search(ExecutionPolicy&& exec,
§ 27.6.13 1202
3 (3.1)
(3.2) 4
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr borrowed_subrange_t<R1>
ranges::search(R1&& r1, R2&& r2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
Returns:
— {i, i + (last2 - first2)}, where i is the first iterator in the range [first1, last1 - (last2
- first2)) such that for every non-negative integer n less than last2 - first2 the condition bool(invoke(pred, invoke(proj1, *(i + n)), invoke(proj2, *(first2 + n))))
is true.
— Returns {last1, last1} if no such iterator exists.
Complexity: At most (last1 - first1) * (last2 - first2) applications of the corresponding predicate and projections.
1
2
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred);
Returns: The first iterator i in the range [first1, last1 - (last2-first2)) such that for every non- negative integer n less than last2 - first2 the following corresponding conditions hold: *(i + n) == *(first2 + n), pred(*(i + n), *(first2 + n)) != false. Returns first1 if [first2, last2) is
empty, otherwise returns last1 if no such iterator is found.
Complexity: At most (last1 - first1) * (last2 - first2) applications of the corresponding
predicate.
5 6
class BinaryPredicate>
ForwardIterator
search_n(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
Size count, const T& value,
BinaryPredicate pred);
Mandates: The type Size is convertible to an integral type (7.3.9, 11.4.8).
Returns: The first iterator i in the range [first, last-count) such that for every non-negative integer n less than count the following corresponding conditions hold: *(i + n) == value, pred(*(i + n), value) != false. Returns last if no such iterator is found.
© ISO/IEC
N4910
template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2,
sentinel_for<I2> S2, class Pred = ranges::equal_to,
class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr subrange<I1>
ranges::search(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<forward_range R1, forward_range R2, class Pred = ranges::equal_to,
class Proj1 = identity, class Proj2 = identity>
template<class ForwardIterator, class Size, class T>
constexpr ForwardIterator
search_n(ForwardIterator first, ForwardIterator last,
Size count, const T& value);
template<class ExecutionPolicy, class ForwardIterator, class Size, class T>
ForwardIterator
search_n(ExecutionPolicy&& exec,
ForwardIterator first, ForwardIterator last,
Size count, const T& value);
template<class ForwardIterator, class Size, class T,
class BinaryPredicate>
constexpr ForwardIterator
search_n(ForwardIterator first, ForwardIterator last,
Size count, const T& value,
BinaryPredicate pred);
template<class ExecutionPolicy, class ForwardIterator, class Size, class T,
§ 27.6.13 1203
8
9
10 11
requires indirectly_comparable<iterator_t<R>, const T*, Pred, Proj>
constexpr borrowed_subrange_t<R>
ranges::search_n(R&& r, range_difference_t<R> count,
const T& value, Pred pred = {}, Proj proj = {});
Returns: {i, i + count} where i is the first iterator in the range [first,last - count) such that for every non-negative integer n less than count, the following condition holds: invoke(pred, invoke(proj, *(i + n)), value). Returns {last, last} if no such iterator is found.
Complexity: At most last - first applications of the corresponding predicate and projection.
7
Complexity: At most last - first applications of the corresponding predicate.
template<forward_iterator I, sentinel_for<I> S, class T,
class Pred = ranges::equal_to, class Proj = identity>
requires indirectly_comparable<I, const T*, Pred, Proj>
constexpr subrange<I>
ranges::search_n(I first, S last, iter_difference_t<I> count,
const T& value, Pred pred = {}, Proj proj = {});
template<forward_range R, class T, class Pred = ranges::equal_to,
class Proj = identity>
1
Proj1 proj1 = {}, Proj2 proj2 = {});
Returns:
ranges::mismatch(std::move(first1), last1, std::move(first2), last2,
pred, proj1, proj2).in2 == last2
27.6.15 Ends with
template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires (forward_iterator<I1> || sized_sentinel_for<S1, I1>) &&
(forward_iterator<I2> || sized_sentinel_for<S2, I2>) &&
indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr bool ranges::ends_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
Let N1 be last1 - first1 and N2 be last2 - first2. Returns: false if N1 < N2, otherwise
ranges::equal(std::move(first1) + (N1 - N2), last1, std::move(first2), last2,
pred, proj1, proj2)
template<input_range R1, input_range R2, class Pred = ranges::equal_to, class Proj1 = identity,
class Proj2 = identity>
requires (forward_range<R1> || sized_range<R1>) &&
(forward_range<R2> || sized_range<R2>) &&
indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr bool ranges::ends_with(R1&& r1, R2&& r2, Pred pred = {},
template<class ForwardIterator, class Searcher>
constexpr ForwardIterator
search(ForwardIterator first, ForwardIterator last, const Searcher& searcher);
Effects: Equivalent to: return searcher(first, last).first;
Remarks: Searcher need not meet the Cpp17CopyConstructible requirements.
27.6.14 Starts with [alg.starts.with]
template<input_iterator I1, sentinel_for<I1> S1, input_iterator I2, sentinel_for<I2> S2,
class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2>
constexpr bool ranges::starts_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
Proj1 proj1 = {}, Proj2 proj2 = {});
template<input_range R1, input_range R2, class Pred = ranges::equal_to, class Proj1 = identity,
class Proj2 = identity>
requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
constexpr bool ranges::starts_with(R1&& r1, R2&& r2, Pred pred = {},
[alg.ends.with]
ranges::copy_n(I first, iter_difference_t<I> n, O result);
Let N be max(0, n).
Mandates: The type Size is convertible to an integral type (7.3.9, 11.4.8).
Effects: For each non-negative integer i < N, performs *(result + i) = *(first + i). Returns:
Proj1 proj1 = {}, Proj2 proj2 = {});
Let N1 be ranges::distance(r1) and N2 be ranges::distance(r2). Returns: false if N1 < N2, otherwise
ranges::equal(ranges::drop_view(ranges::ref_view(r1), N1 - N2), r2, pred, proj1, proj2)
int main(){
cout << n4910 << endl;
return EXIT_SUCCESS;
}
編纂・実行結果(compile and go)
bash
検討事項(agenda)
コンパイルエラーを取るか、コンパイルエラーの理由を解説する。
参考資料(reference)
関連する自己参照以外は、こちらの先頭に移転。
C言語（C++)に対する誤解、曲解、無理解、爽快。
#include "N4910.h"
C++N4910資料の改善点
dockerにclang
docker gnu(gcc/g++) and llvm(clang/clang++)
コンパイル用shell script C版(clangとgcc)とC++版(clang++とg++)
C++N4910:2022 tag follower 300人超えました。ありがとうございます。
astyle 使ってみた
DoCAP（ドゥーキャップ）って何ですか？
小川メソッド 覚え（書きかけ）
＜この記事は個人の過去の経験に基づく個人の感想です。現在所属する組織、業務とは関係がありません。＞
文書履歴(document history)
ver. 0.01 初稿 20220814