Effective C++: 55 Specific Ways to Improve Your Programs and DesignsThird version by Scott Mayers
https://www.informit.com/store/effective-c-plus-plus-55-specific-ways-to-improve-your-9780321334879
https://www.amazon.com/dp/0321334876
Sample code from
Yuzhen11/Effective_CPP
https://github.com/Yuzhen11/Effective_CPP
目的(purpose)
"Effective C++コンパイル記録は、コンパイラおよび対応標準により、コンパイルエラーMessageの違いを記録し、どのエラーが出たら、どの対応標準にすればエラーが少なくなるかを考察するための資料の第一歩です。
上記参照サイトにはコンパイルする仕組みを提供していない。簡易な台本(script)を作成する。
成果(outcome)
計画(plan)
(1)コンパイラの種類、対応標準の違いによってエラーの数が違う。
(2)同じエラー、警告であってもMessageの表現が違う。
(3) エラー、警告のMessageをネットで検索する際に役立てる。
(4)コード断片の役に立つまたは意味のあるコンパイル・リンク・実行エラーの取り方を検討する
(5)コード断片の役に立つまたは意味のある出力を検討する
結果(result)現在整理中
1) コンパイラによるエラー、渓谷の違い
2) コンパイラによる必要なヘッダファイルの違い
3) 参考にした資料
算譜(source code)
///Effective C++: 55 Specific Ways to Improve Your Programs and DesignsThird version by Scott Mayers
///https://www.informit.com/store/effective-c-plus-plus-55-specific-ways-to-improve-your-9780321334879
#include <iostream>
#include <cstdlib>
using namespace std;
const char * msg ="Item 2: Prefer consts, enums, and inlines to #defines.";
/// From here "Effective C++
///Prefer compiler to preprocessor. #define will be handled be preprocessor.
#define ASPECT_RATIO 1.653
///The name may not get entered into the symbol table. Debug is hard!
///prefer using const
const double AspectRatio = 1.653;
///Two sepecial cases:
///pointer
namespace A { /// add for redefinition
const char* const authorName = "Scott Meyers"; // const pointer to const char
}/// add namespace A
// May prefer using std::string
namespace B { /// add for redefinition
const std::string authorName("Scott Meyers");
///class-specific constants
///Take it a member and make it static.
class GamePlayer {
private:
static const int NumTurns = 5; // constant declaration
int scores[NumTurns];
};
///For integral type (e.g., integers, chars, bools), as long as you don't take their address, you can declare them and use them without providing a definition.
///If you really want, no initial value is permitted at the point of definition.
const int GamePlayer::NumTurns; // definition of NumTurns`
///Older compiler may not accept the syntax above and above syntax only works for integral types.
} /// add namespace B
class CostEstimate {
private:
static const double FudgeFactor; // declaration, in hpp
};
const double CostEstimate::FudgeFactor = 1.35; // definition,in cpp
///But what if you want to know the value during compilatoin of the class (e.g. Define the length of an array)? Use "the enum hack".
class GamePlayer {
private:
enum {NumTurns = 5};
int scores[NumTurns];
};
///The enum hack is worth konwing about for several resons.
///In some ways more like a #define than a const does. No legal to take address, no storage.
///Lots of code employs it.
///What about using #define to implement functions?
#define CALL_WITH_MAX(a,b) f((a)>(b) ? (a):(b))
///Remember to parenthesize all the arguments in the macro body.
///And werid things may still happen.
void f(int a) { /// add f()definition
cout<<"MAX="<<a<<endl;///
}///
void g() { /// add g()
int a = 5, b = 0;
CALL_WITH_MAX(++a, b); // a is incremented twice
CALL_WITH_MAX(++a, b+10); // a is incremented once
///The number of times that a is incremented before calling f depends on what it is being compared with!
}///
///inline may be a better choice.
template<typename T>
inline void callWithMax(const T& a, const T& b) {
f(a > b ? a : b);
}
///Things to Remember
///For simple constants, prefer const objects or enums to #defines.
///For function-like marcos, prefer inline functions to #defines.
/// to here from "Effective C++"
int main() {
g();
cout << msg << endl;
return EXIT_SUCCESS;
}
編纂・実行結果(compile and go)
$ ../cpa.sh i2
$ clang++ i2.cpp -I./ -std=c++14 -Wall
i2.cpp:15:14: warning: unused variable 'AspectRatio' [-Wunused-const-variable]
const double AspectRatio = 1.653;
^
i2.cpp:20:19: warning: unused variable 'authorName' [-Wunused-const-variable]
const char* const authorName = "Scott Meyers"; // const pointer to const char
^
i2.cpp:32:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
i2.cpp:56:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
4 warnings generated.
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
$ clang++ i2.cpp -I./ -std=c++17 -Wall
i2.cpp:15:14: warning: unused variable 'AspectRatio' [-Wunused-const-variable]
const double AspectRatio = 1.653;
^
i2.cpp:20:19: warning: unused variable 'authorName' [-Wunused-const-variable]
const char* const authorName = "Scott Meyers"; // const pointer to const char
^
i2.cpp:32:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
i2.cpp:56:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
4 warnings generated.
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
$ clang++ i2.cpp -I./ -std=c++2a -Wall
i2.cpp:15:14: warning: unused variable 'AspectRatio' [-Wunused-const-variable]
const double AspectRatio = 1.653;
^
i2.cpp:20:19: warning: unused variable 'authorName' [-Wunused-const-variable]
const char* const authorName = "Scott Meyers"; // const pointer to const char
^
i2.cpp:32:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
i2.cpp:56:9: warning: private field 'scores' is not used [-Wunused-private-field]
int scores[NumTurns];
^
4 warnings generated.
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
$ g++-8 i2.cpp -I./ -std=c++14 -Wall
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
$ g++-8 i2.cpp -I./ -std=c++17 -Wall
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
$ g++-8 i2.cpp -I./ -std=c++2a -Wall
MAX=7
MAX=10
Item 2: Prefer consts, enums, and inlines to #defines.
参考資料(reference)
Effective C++(項1〜5)解説
https://qiita.com/MoriokaReimen/items/58f183d421bb932cbbda
Effective C++ Third version, sample code compile list(まとめ
https://qiita.com/kaizen_nagoya/items/2092638c221e1033040c
docker gnu(gcc/g++) and llvm(clang/clang++)
https://qiita.com/drafts/059874ea39c4de64c0f7
[C][C++]の国際規格案の例題をコンパイルするときの課題7つ。
https://qiita.com/kaizen_nagoya/items/5f4b155030259497c4de
C++N4606 Working Draft 2016, ISO/IEC 14882, C++ standardのコード断片をコンパイルするためにしていること
https://qiita.com/kaizen_nagoya/items/a8d7ee2f2e29e76c19c1
コンパイル用shell script C版(clangとgcc)とC++版(clang++とg++)
https://qiita.com/kaizen_nagoya/items/74220c0577a512c2d7da
Clang/Clang++(LLVM) gcc/g++(GNU) コンパイラ警告等比較
https://qiita.com/kaizen_nagoya/items/9a82b958cc3aeef0403f
C++2003とC++2017でコンパイルエラーになるならない事例集
https://qiita.com/kaizen_nagoya/items/a13ea3823441c430edff
Qiitaに投稿するCのStyle例(暫定)
https://qiita.com/kaizen_nagoya/items/946df1528a6a1ef2bc0d
cpprefjpのdecltypeをコンパイル試験
https://qiita.com/kaizen_nagoya/items/090909af702f0d5d8a67
MISRA C++ 5-0-16
https://qiita.com/kaizen_nagoya/items/7df2d4e05db724752a74
C++ Templates Part1 BASICS Chapter 3. Class Templates 3.2 Use of Class Template Stack stack1test.cpp
https://qiita.com/kaizen_nagoya/items/cd5fc49106fad5a4e9ed
ISO/IEC TS 17961:2013 C Secure Coding Rules(1) All list(to be confirmed)
https://qiita.com/kaizen_nagoya/items/54e056195c4f11b850a1
C言語(C++)に対する誤解、曲解、無理解、爽快。
https://qiita.com/kaizen_nagoya/items/3f3992c9722c1cee2e3a
C Puzzle Bookの有り難み5つ、C言語規格及びCコンパイラの特性を認識
https://qiita.com/kaizen_nagoya/items/d89a48c1536a02ecdec9
'wchar.h' file not found で困った clang++ macOS
https://qiita.com/kaizen_nagoya/items/de15cd46d657517fac11
Open POSIX Test Suiteの使い方を調べはじめました
https://qiita.com/kaizen_nagoya/items/644d5e407f5faf96e6dc
MISRA-C 2012 Referenceに掲載している文献の入手可能性を確認
https://qiita.com/kaizen_nagoya/items/96dc8b125e462d5575bb
どうやって MISRA Example Suiteをコンパイルするか
https://qiita.com/kaizen_nagoya/items/fbdbff5ff696e2ca7f00
MISRA C まとめ #include
https://qiita.com/kaizen_nagoya/items/f1a79a7cbd281607c7c9
「C++完全理解ガイド」の同意できること上位10
https://qiita.com/kaizen_nagoya/items/aa5744e0c4a8618c7671
C++参考資料一覧
https://researchmap.jp/joub9b3my-1797580/#_1797580
文書履歴(document history)
ver. 0.10 初稿 20180619
ver. 0.11 参考文献追記 20180620
ver. 0.12 参考文献追記 20180623