Defined in header <type_traits> template< class T > struct is_function; (since C++11) Checks whether T is a function type (not std::function). Provides the member constant value which is equal to true, if T is a function type. Otherwise, value is equal to false. Template parameters T - a type to check Helper variable template template< class T > constexpr bool is_function_v = is_function<T>::value; (since C++17) Inherited from st

Defined in header <type_traits> template< class T > struct is_floating_point; (since C++11) Checks whether T is a floating-point type. Provides the member constant value which is equal to true, if T is the type float, double, long double, including any cv-qualified variants. Otherwise, value is equal to false. Template parameters T - a type to check Helper variable template template< class T > constexpr bool is_floating_point_v = is_floating_poi

Defined in header <type_traits> template< class T > struct is_final; (since C++14) If T is a final class (that is, a class declared with the final specifier), provides the member constant value equal true. For any other type, value is false. If T is a class type, T shall be a complete type; otherwise, the behavior is undefined. Template parameters T - a type to check Helper variable template template< class T > constexpr bool is_final_v = is_fin

Defined in header <future> template<> struct is_error_condition_enum<std::future_errc> : std::true_type; (since C++11) Specifies that std::future_errc is an error condition enum. This enables std::error_code and std::error_condition automatic conversions. See also is_error_condition_enum (C++11) identifies an enumeration as an std::error_condition (class template)

Defined in header <system_error> template<> struct is_error_condition_enum<std::errc> : std::true_type; (since C++11) Specifies that std::errc is an error condition enum. This enables std::error_code and std::error_condition automatic conversions. Inherited from std::integral_constant Member constants value [static] true (public static member constant) Member functions operator bool converts the object to bool, returns value (public member func

Defined in header <system_error> template< class T > struct is_error_condition_enum; (since C++11) If T is an error condition enum, this template provides the member constant value equal true. For any other type, value is false. This template may be specialized for a user-defined type to indicate that the type is eligible for std::error_code and std::error_condition automatic conversions. The following class of the standard library is an error condition enum: std::err

Defined in header <ios> template< > struct is_error_code_enum<std::io_errc> : public std::true_type { }; (since C++11) This specialization of std::is_error_code_enum informs other library components that values of type std::io_errc are enumerations that hold error codes, which makes them implicitly convertible and assignable to objects of type std::error_code. Inherited from std::integral_constant Member constants value [static] true (public static m

Defined in header <system_error> template< class T > struct is_error_code_enum; (since C++11) If T is an error code enumeration, this template provides the member constant value equal true. For any other type, value is false. This template may be specialized for a user-defined type to indicate that the type is eligible for std::error_code and std::error_condition automatic conversions. The following classes of the standard library are an error code enum: std::io_errc

Defined in header <type_traits> template< class T > struct is_enum; (since C++11) Checks whether T is an enumeration type. Provides the member constant value which is equal to true, if T is an enumeration type . Otherwise, value is equal to false. Template parameters T - a type to check Helper variable template template< class T > constexpr bool is_enum_v = is_enum<T>::value; (since C++17) Inherited from std::integral_constant

Defined in header <type_traits> template< class T > struct is_empty; (since C++11) If T is an empty type (that is, a non-union class type with no non-static data members other than bit-fields of size 0, no virtual functions, no virtual base classes, and no non-empty base classes), provides the member constant value equal true. For any other type, value is false. If T is a non-union class type, T shall be a complete type; otherwise, the behavior is undefined. Templat