std::is_reference
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| Defined in header <type_traits>
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| template< class T > struct is_reference; |
(C + + 11以来) | |
Tが参照型(左辺値参照または右辺値参照)である場合、メンバーが一定提供value等しいtrueを。その他のタイプのために、valuefalseです.Original:
If
T is a reference type (lvalue reference or rvalue reference), provides the member constant value equal true. For any other type, value is false.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
目次 |
Inherited from std::integral_constant
Member constants
| value [静的] |
true T is a reference type もし、そうでなければfalse Original: true if T is a reference type , false otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (公共の静的メンバ定数) |
Member functions
| operator bool |
boolにオブジェクトは、 value返しに変換します Original: converts the object to bool, returns value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (パブリックメンバ関数) |
Member types
| タイプ
Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
Definition |
value_type
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bool
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type
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std::integral_constant<bool, value> |
[編集] 可能な実装
template <class T> struct is_reference : std::false_type {}; template <class T> struct is_reference<T&> : std::true_type {}; template <class T> struct is_reference<T&&> : std::true_type {}; |
[編集] 例
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_reference<A>::value << '\n'; std::cout << std::is_reference<A&>::value << '\n'; std::cout << std::is_reference<A&&>::value << '\n'; std::cout << std::is_reference<int>::value << '\n'; std::cout << std::is_reference<int&>::value << '\n'; std::cout << std::is_reference<int&&>::value << '\n'; }
Output:
false true true false true true
[編集] も参照してください
| (C++11) |
タイプかどうかをチェックするには、左辺値参照'です Original: checks if a type is lvalue reference 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) |
| (C++11) |
タイプかどうかをチェックするには、で右辺値参照 Original: checks if a type is rvalue reference 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) |