Section 3: library functions
std::initializer_list<T>::begin – std::initializer_list<T>::begin Synopsis const T *begin() const noexcept; (since C++ 11)(until C++ 14) constexpr const T *begin() const noexcept; (since C++ 14) Returns a pointer to the first element in the initializer list. If the initializer list is empty, the values of begin() and end() are unspecified, but will be identical. Parameters (none) Return…
std::initializer_list – std::initializer_list Synopsis Defined in header <initializer_list> template< class T > (since C++11) class initializer_list; An object of type std::initializer_list<T> is a lightweight proxy object that provides access to an array of objects of type const T. A std::initializer_list object is automatically constructed when: * a braced-init-list is used to list-initialize an object, where…
std::indirect_array<T>::operator= – std::indirect_array<T>::operator= Synopsis void operator=(const T &value) const; (1) void operator=(const std::valarray<T> &val_arr) const; (2) const indirect_array & operator=(const indirect_array &sl_arr) const; (3)(since C++ 11) Assigns values to all referred elements. 1) Assigns value to all of the elements. 2) Assigns the elements of val_arr to the referred to elements of *this. 3) Assigns…
std::indirect_array<T>::~indirect_array – std::indirect_array<T>::~indirect_array Synopsis ~indirect_array(); Destroys the indexes in the array. The elements referred to by the object are not modified.
std::indirect_array – std::indirect_array Synopsis Defined in header <valarray> template< class T > class indirect_array; std::gslice_array is a helper template used by std::indirect_array subscript operator. It has reference semantics to a subset of the array specified by an indirect array (std::valarray<std::size_t> object). Member types Type Definition value_type T Member functions constructs a indirect_array constructor (public member…
std::independent_bits_engine<Engine,W,UIntType>::seed – std::independent_bits_engine<Engine,W,UIntType>::seed Synopsis void seed(); (1)(since C++ 11) void seed(result_type value); (2)(since C++ 11) template <class Sseq> (3)(since C++ 11) void seed(Sseq &seq); Reinitializes the internal state of the underlying engine using a new seed value. 1) Seeds the underlying engine with the default seed value. Effectively calls e.seed(), where e is the underlying…
std::incrementable_traits – std::incrementable_traits Synopsis Defined in header<iterator> template <class I> (1)(since C++ 20) struct incrementable_traits { }; template <class T> requires std::is_object_v<T>(2) (since C++ 20) struct incrementable_traits<T *>; template <class T> (3)(since C++ 20) struct incrementable_traits<const T> : incrementable_traits<T> { }; template <class T> requires requires { typename T::difference_type; } (4)(since C++ 20) struct incrementable_traits<T>;…
std::inclusive_scan – std::inclusive_scan Synopsis Defined in header <numeric> template< class InputIt, class OutputIt > OutputIt inclusive_scan( InputIt first, (1) (since C++17) InputIt last, OutputIt d_first ); template< class ExecutionPolicy, class ForwardIt1, class ForwardIt2 > ForwardtIt2 inclusive_scan( ExecutionPolicy&& policy, ForwardIt1 first, (2) (since C++17) ForwardIt1 last, ForwardIt2 d_first ); template< class InputIt, class OutputIt, class BinaryOperation…
std::includes – std::includes Synopsis Defined in header <algorithm> template< class InputIt1, class InputIt2 > bool includes( InputIt1 first1, InputIt1 last1, (until C++20) InputIt2 first2, InputIt2 last2 ); template< class InputIt1, class InputIt2 > constexpr bool includes( InputIt1 first1, InputIt1 last1, (since C++20) InputIt2 first2, InputIt2 last2 ); template< class ExecutionPolicy, class ForwardIt1, class ForwardIt2 >…
std::in_place,std::in_place_type,std::in_place_index,std::in_place_t,std::in_place_type_t,std::in_place_index_t – std::in_place,std::in_place_type,std::in_place_index,std::in_place_t,std::in_place_type_t,std::in_place_index_t Synopsis Defined in header<utility> struct in_place_t { explicit in_place_t() = default; (since C++ 17) }; inline constexpr in_place_t in_place{}; template <class T> struct in_place_type_t { explicit in_place_type_t() = default; }; (since C++ 17) template <class T> inline constexpr in_place_type_t<T> in_place_type{}; template <std::size_t I> struct in_place_index_t { explicit in_place_index_t() = default; }; (since…
std::in_place,std::in_place_type,std::in_place_index,std::in_place_t, – std::in_place,std::in_place_type,std::in_place_index,std::in_place_t, Synopsis Defined in header<utility> struct in_place_t { explicit in_place_t() = default; (since C++ 17) }; inline constexpr in_place_t in_place{}; template <class T> struct in_place_type_t { explicit in_place_type_t() = default; }; (since C++ 17) template <class T> inline constexpr in_place_type_t<T> in_place_type{}; template <std::size_t I> struct in_place_index_t { explicit in_place_index_t() = default; }; (since…
std::imag(std::complex) – std::imag(std::complex) Synopsis Defined in header<complex> template <class T> (until C++ 14) T imag(const std::complex<T> &z); template <class T> (since C++ 14) constexpr T imag(const std::complex<T> &z); float imag(float z); template <class DoubleOrInteger> (1)(since C++ 11) double imag(DoubleOrInteger z); (until C++ 14) long double imag(long double z); (2) constexpr float imag(float z); template <class…
std::ilogb,std::ilogbf,std::ilogbl – std::ilogb,std::ilogbf,std::ilogbl Synopsis Defined in header<cmath> int ilogb(float arg); (1)(since C++ 11) int ilogbf(float arg); int ilogb(double arg); (2)(since C++ 11) int ilogb(long double arg); (3)(since C++ 11) int ilogbl(long double arg); int ilogb(IntegralType arg); (4)(since C++ 11) #define FP_ILOGB0 /*implementation-defined*/ (5)(since C++ 11) #define FP_ILOGBNAN /*implementation-defined*/ (6)(since C++ 11) 1-3) Extracts the value…
std::ignore – std::ignore Synopsis Defined in header <tuple> const /*unspecified*/ ignore; (since C++11) (until C++17) inline constexpr /*unspecified*/ ignore; (since C++17) An object of unspecified type such that any value can be assigned to it with no effect. Intended for use with std::tie when unpacking a std::tuple, as a placeholder for the arguments that are…
std::basic_ifstream – std::basic_ifstream Synopsis Defined in header <fstream> template< class CharT, class Traits = std::char_traits<CharT> > class basic_ifstream : public std::basic_istream<CharT, Traits> The class template basic_ifstream implements high-level input operations on file based streams. It interfaces a file-based streambuffer (std::basic_filebuf) with the high-level interface of (std::basic_istream). A typical implementation of std::basic_ifstream holds only one non-derived…
std::identity – std::identity Synopsis Defined in header <functional> struct identity; (since C++20) std::identity is a function object type whose operator() returns its argument unchanged. Member types Member type Definition is_transparent /* unspecified */ Member functions returns the argument unchanged operator() (public member function) std::identity::operator() template< class T> constexpr T&& operator()( T&& t ) const noexcept;…
std::hypot,std::hypotf,std::hypotl – std::hypot,std::hypotf,std::hypotl Synopsis Defined in header <cmath> float hypot ( float x, float y ); (1) (since C++11) float hypotf( float x, float y ); double hypot ( double x, double y ); (2) (since C++11) long double hypot ( long double x, long double y ); (3) (since C++11) long double hypotl( long…
std::holds_alternative – std::holds_alternative Synopsis Defined in header<variant> template <class T, class… Types> (since C++ 17) constexpr bool holds_alternative(const std::variant<Types…> &v) noexcept; Checks if the variant v holds the alternative T. The call is ill-formed if T does not appear exactly once in Types… Parameters v – variant to examine Return value true if the variant…
std::hermite,std::hermitef,std::hermitel – std::hermite,std::hermitef,std::hermitel Synopsis double hermite(unsigned int n, double x); float hermite(unsigned int n, float x); long double hermite(unsigned int n, long double x); (1)(since C++ 17) float hermitef(unsigned int n, float x); long double hermitel(unsigned int n, long double x); double hermite(unsigned int n, IntegralType x); (2)(since C++ 17) 1) Computes the (physicist’s) Hermite_polynomials…
std::hash<std::variant> – std::hash<std::variant> Synopsis Defined in header<variant> template <class… Types> (since C++ 17) struct hash<std::variant<Types…>>; The template specialization of std::hash for the std::variant template allows users to obtain hashes of variant objects. The specialization std::hash<std::variant<Types…>> is enabled (see std::hash) if every specialization in std::hash<std::remove_const_t<Types>>… is enabled, and is disabled otherwise. The member functions of this…