std::is_function
Материал из cppreference.com
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| Заголовочный файл <type_traits>
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| template< class T > struct is_function; |
(начиная с C++11) | |
Если
T является функцией типа (но не std::function, лямбда-выражения или другой вызываемый тип объекта), обеспечивает постоянный член value равных true. Для любого другого типа, value является false.Original:
If
T is function type (but not std::function, lambda expression or another callable object type), 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.
Содержание |
Унаследован от std::integral_constant
Member constants
| value [static] |
true если T is a function type , false иначе Original: true if T is a function 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. (public static константа-член) |
Member functions
| operator bool |
преобразует объект в bool, возвращает value 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. (public функция-член) |
Member types
| Type
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> |
[править] Пример
#include <iostream> #include <type_traits> struct A {}; int f() { return 1; } int main() { std::cout << std::boolalpha; std::cout << std::is_function<A>::value << '\n'; std::cout << std::is_function<int(int)>::value << '\n'; std::cout << std::is_function<decltype(f)>::value << '\n'; std::cout << std::is_function<int>::value << '\n'; }
Вывод:
false true true false
[править] См. также
| (C++11) |
проверяет, является ли тип объекта типа Original: checks if a type is object type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (шаблон класса) |
| (C++11) |
checks if a type is a class type (but not union type) (шаблон класса) |