名前空間
変種
操作

Static Assertion

提供: cppreference.com
< cpp‎ | language

 
 
C + +言語
一般的なトピック
Original:
General topics
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
フロー制御
Original:
Flow control
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
条件付き実行文
Original:
Conditional execution statements
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
繰り返し文
Original:
Iteration statements
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
文をジャンプします
Original:
Jump statements
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
機能します
Original:
Functions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
関数の宣言
ラムダ関数の宣言
関数テンプレート
の歴史。インライン指定
例外仕様 (廃止予定)
noexcept指定子 (C++11)
例外
Original:
Exceptions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
名前空間
Original:
Namespaces
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
タイプ
Original:
Types
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
decltype specifier (C++11)
指定子
Original:
Specifiers
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
CV指定
貯蔵期間指定
constexprの指定子 (C++11)
自動指定 (C++11)
alignas指定子 (C++11)
初期化
Original:
Initialization
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
リテラル
Original:
Literals
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
Original:
Expressions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
代替表現
ユーティリティ
Original:
Utilities
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
タイプ
Original:
Types
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
typedef declaration
型の別名宣言 (C++11)
属性 (C++11)
キャストします
Original:
Casts
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
暗黙の型変換
const_cast conversion
static_cast conversion
dynamic_cast conversion
reinterpret_cast conversion
Cスタイルキャストと機能
メモリの割り当て
Original:
Memory allocation
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
クラス
Original:
Classes
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
クラス固有の機能特性
Original:
Class-specific function properties
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
明示 (C++11)
静的
特殊なメンバ関数
Original:
Special member functions
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
テンプレート
Original:
Templates
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
クラステンプレート
関数テンプレート
テンプレートの特殊化
パラメーターパック (C++11)
その他
Original:
Miscellaneous
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
インラインアセンブリ
 
コンパイル時にアサーション·チェックを実行します
Original:
Performs compile-time assertion checking
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

目次

[編集] 構文

static_assert ( bool_constexpr , string ) (C + + 11以来)

[編集] 説明

  • bool_constexprブール定数式が評価される
    Original:
    bool_constexpr a boolean constant expression to be evaluated
    The text has been machine-translated via Google Translate.
    You can help to correct and verify the translation. Click here for instructions.
  • stringがfalseの場合は、コンパイラエラーとして表示されるリテラル文字列bool_constexpr
    Original:
    string string literal that will appear as compiler error if bool_constexpr is false
    The text has been machine-translated via Google Translate.
    You can help to correct and verify the translation. Click here for instructions.

[編集]

#include <type_traits>
 
template<class T>
    void swap( T& a, T& b)
    {
        static_assert(std::is_copy_constructible<T>::value,
                      "Swap requires copying");
 
        auto c = b;
        b = a;
        a = c;
    }
 
template<class T>
    struct data_structure
{
    static_assert(std::is_default_constructible<T>::value,
                  "Data Structure requires default-constructible elements");
 
};
 
struct no_copy
{
    no_copy ( const no_copy& ) = delete;
    no_copy () = default;
};
 
struct no_default
{
    no_default ( ) = delete;
};
 
int main()
{
    int a, b;
    swap(a,b);
 
    no_copy nc_a, nc_b;
    swap(nc_a,nc_b); // 1
 
    data_structure<int> ds_ok;
    data_structure<no_default> ds_error; // 2
}

Possible output:

1: error: static assertion failed: Swap requires copying
2: error: static assertion failed: Data Structure requires default-constructible elements

[編集] も参照してください