Section 3: library functions
std::is_floating_point – std::is_floating_point Synopsis Defined in header<type_traits> template <class T> (since C++ 11) struct is_floating_point; 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 –…
std::is_final – std::is_final Synopsis Defined in header<type_traits> template <class T> (since C++ 14) struct is_final; 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;…
std::is_execution_policy – std::is_execution_policy Synopsis Defined in header<execution> template <class T> (since C++ 17) struct is_execution_policy; Checks whether T is a standard or implementation-defined execution policy type. Provides the member constant value which is equal to true, if T is a_standard_execution_policy_type, or an implementation-defined execution policy type. Otherwise, value is equal to false. The behavior of…
std::is_error_condition_enum<std::errc> – std::is_error_condition_enum<std::errc> Synopsis Defined in header<system_error> template <> (since C++ 11) struct is_error_condition_enum<std::errc> : std::true_type; Specifies that std::errc is an error condition enum. This enables implicit conversion to std::error_condition. Inherited from std::integral_constant Member constants value true (public static member constant) [static] Member functions converts the object to bool, returns value operator bool (public member…
std::is_error_code_enum<std::io_errc> – std::is_error_code_enum<std::io_errc> Synopsis Defined in header<ios> template <> (since C++ 11) struct is_error_code_enum<std::io_errc> : public std::true_type { }; 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…
std::is_eq,std::is_neq,std::is_lt,std::is_gt,std::is_lteq,std::is_gteq – std::is_eq,std::is_neq,std::is_lt,std::is_gt,std::is_lteq,std::is_gteq Synopsis Defined in header <compare> constexpr bool is_eq(std::weak_equality cmp) noexcept; (1) (since C++20) constexpr bool is_neq(std::weak_equality cmp) noexcept; (2) (since C++20) constexpr bool is_lt(std::partial_ordering cmp) noexcept; (3) (since C++20) constexpr bool is_lteq(std::partial_ordering cmp) noexcept; (4) (since C++20) constexpr bool is_gt(std::partial_ordering cmp) noexcept; (5) (since C++20) constexpr bool is_gteq(std::partial_ordering cmp) noexcept (6) (since…
std::is_enum – std::is_enum Synopsis Defined in header<type_traits> template <class T> (since C++ 11) struct is_enum; 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…
std::is_empty – std::is_empty Synopsis Defined in header<type_traits> template <class T> (since C++ 11) struct is_empty; 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…
std::is_destructible< _Tp > – Synopsis Inherits std::integral_constant< bool,(__is_destructible_safe< _Tp >::value)>. Public Types typedef integral_constant < bool, __v > type" typedef bool value_type Public Member Functions constexpr operator value_type () Static Public Attributes static constexpr bool value Detailed Description template<typename _Tp>struct std::is_destructible< _Tp > is_destructible Definition at line 652 of file type_traits. Author Generated automatically by…
std::is_destructible,std::is_trivially_destructible,std::is_nothrow_destructible – std::is_destructible,std::is_trivially_destructible,std::is_nothrow_destructible Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_destructible; template <class T> (2)(since C++ 11) struct is_trivially_destructible; template <class T> (3)(since C++ 11) struct is_nothrow_destructible; 1) If an imaginary struct containing a member object of type T has a non-deleted destructor, provides the member constant value equal true. For…
std::is_default_constructible< _Tp > – Synopsis Inherits std::integral_constant< bool,(__is_default_constructible_safe< _Tp >::value)>. Inherited by std::__is_constructible_impl< _Tp >. Public Types typedef integral_constant < bool, __v > type" typedef bool value_type Public Member Functions constexpr operator value_type () Static Public Attributes static constexpr bool value Detailed Description template<typename _Tp>struct std::is_default_constructible< _Tp > is_default_constructible Definition at line 748 of file…
std::is_default_constructible,std::is_trivially_default_constructible,std::is_nothrow_default_constructible – std::is_default_constructible,std::is_trivially_default_constructible,std::is_nothrow_default_constructible Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_default_constructible; template <class T> (2)(since C++ 11) struct is_trivially_default_constructible; template <class T> (3)(since C++ 11) struct is_nothrow_default_constructible; 1) If std::is_constructible<T>::value is true, provides the member constant value equal to true, otherwise value is false. 2) If std::is_trivially_constructible<T>::value is true, provides the…
std::is_default_constructible,std::is_trivially_default_constructible, – std::is_default_constructible,std::is_trivially_default_constructible, Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_default_constructible; template <class T> (2)(since C++ 11) struct is_trivially_default_constructible; template <class T> (3)(since C++ 11) struct is_nothrow_default_constructible; 1) If std::is_constructible<T>::value is true, provides the member constant value equal to true, otherwise value is false. 2) If std::is_trivially_constructible<T>::value is true, provides the member constant…
std::is_copy_constructible< _Tp > – Synopsis Inherits std::__is_copy_constructible_impl< _Tp, bool >. Inherited by std::__is_copy_insertable< allocator< _Tp > >. Detailed Description template<typename _Tp>struct std::is_copy_constructible< _Tp > is_copy_constructible Definition at line 974 of file type_traits. Author Generated automatically by Doxygen for libstdc++ from the source code.
std::is_copy_constructible,std::is_trivially_copy_constructible,std::is_nothrow_copy_constructible – std::is_copy_constructible,std::is_trivially_copy_constructible,std::is_nothrow_copy_constructible Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_copy_constructible; template <class T> (2)(since C++ 11) struct is_trivially_copy_constructible; template <class T> (3)(since C++ 11) struct is_nothrow_copy_constructible; 1) If T is not a referenceable type (i.e., possibly cv-qualified void or a function type with a cv-qualifier-seq or a ref-qualifier), provides a…
std::is_copy_constructible,std::is_trivially_copy_constructible, – std::is_copy_constructible,std::is_trivially_copy_constructible, Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_copy_constructible; template <class T> (2)(since C++ 11) struct is_trivially_copy_constructible; template <class T> (3)(since C++ 11) struct is_nothrow_copy_constructible; 1) If T is not a referenceable type (i.e., possibly cv-qualified void or a function type with a cv-qualifier-seq or a ref-qualifier), provides a member constant…
std::is_copy_assignable< _Tp > – Synopsis Inherits std::__is_copy_assignable_impl< _Tp, bool >. Detailed Description template<typename _Tp>struct std::is_copy_assignable< _Tp > is_copy_assignable Definition at line 1118 of file type_traits. Author Generated automatically by Doxygen for libstdc++ from the source code.
std::is_copy_assignable,std::is_trivially_copy_assignable,std::is_nothrow_copy_assignable – std::is_copy_assignable,std::is_trivially_copy_assignable,std::is_nothrow_copy_assignable Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_copy_assignable; template <class T> (2)(since C++ 11) struct is_trivially_copy_assignable; template <class T> (3)(since C++ 11) struct is_nothrow_copy_assignable; 1) If T is not a referenceable type (i.e., possibly cv-qualified void or a function type with a cv-qualifier-seq or a ref-qualifier), provides a…
std::is_copy_assignable,std::is_trivially_copy_assignable, – std::is_copy_assignable,std::is_trivially_copy_assignable, Synopsis Defined in header<type_traits> template <class T> (1)(since C++ 11) struct is_copy_assignable; template <class T> (2)(since C++ 11) struct is_trivially_copy_assignable; template <class T> (3)(since C++ 11) struct is_nothrow_copy_assignable; 1) If T is not a referenceable type (i.e., possibly cv-qualified void or a function type with a cv-qualifier-seq or a ref-qualifier), provides a member constant…
std::is_convertible< _From, _To > – Synopsis Inherits std::integral_constant< bool, __is_convertible_helper< _From, _To >::value >. Public Types typedef integral_constant < bool, __v > type" typedef bool value_type Public Member Functions constexpr operator value_type () Static Public Attributes static constexpr bool value Detailed Description template<typename _From, typename _To>struct std::is_convertible< _From, _To > is_convertible Definition at line 1317…