std::is_pointer
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| Defined in header <type_traits>
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| template< class T > struct is_pointer; |
(C + + 11以来) | |
Tは、オブジェクトのポインタ型や関数ポインタ型(ただし、非静的メンバオブジェクトまたはメンバ関数へのポインタ)である場合、メンバー定数value等しいtrueを提供しています。その他のタイプのために、valuefalseです.Original:
If
T is an object pointer type or a function pointer type (but not pointer to non-static member object or member function), 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 pointer type もし、そうでなければfalse Original: true if T is a pointer 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_pointer_helper : std::false_type {}; template< class T > struct is_pointer_helper<T*> : std::true_type {}; template< class T > struct is_pointer : is_pointer_helper<typename std::remove_cv<T>::type> {}; |
[編集] 例
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_pointer<A>::value << '\n'; std::cout << std::is_pointer<A*>::value << '\n'; std::cout << std::is_pointer<float>::value << '\n'; std::cout << std::is_pointer<int>::value << '\n'; std::cout << std::is_pointer<int*>::value << '\n'; std::cout << std::is_pointer<int**>::value << '\n'; }
Output:
false true false 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、配列型です Original: checks if a type is an array type 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、スカラー型である Original: checks if a type is scalar type 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) |