Section 3: library functions
std::clock – std::clock Synopsis Defined in header <ctime> std::clock_t clock(); Returns the approximate processor time used by the process since the beginning of an implementation-defined era related to the program’s execution. To convert result value to seconds divide it by CLOCKS_PER_SEC. Only the difference between two values returned by different calls to std::clock is meaningful,…
std::clearerr – std::clearerr Synopsis Defined in header<cstdio> void clearerr(std::FILE *stream); Resets the error flags and the EOF indicator for the given file stream. Parameters stream – the file to reset the error flags for Return value (none) Example This section is incomplete Reason: no example See also checks for the end-of-file feof (function) displays a…
std::clamp – std::clamp Synopsis Defined in header<algorithm> template <class T> (1)(since C++ 17) constexpr const T &clamp(const T &v, const T &lo, const T &hi); template <class T, class Compare> (2)(since C++ 17) constexpr const T &clamp(const T &v, const T &lo, const T &hi, Compare comp); 1) If v compares less than lo, returns…
std::cin,std::wcin – std::cin,std::wcin Synopsis Defined in header <iostream> extern std::istream cin; (1) extern std::wistream wcin; (2) The global objects std::cin and std::wcin control input from a stream buffer of implementation-defined type (derived from std::streambuf), associated with the standard C input stream stdin. These objects are guaranteed to be initialized during or before the first time…
std::chrono::zoned_traits – std::chrono::zoned_traits Synopsis Defined in header<chrono> template <class TimeZonePtr> (1)(since C++ 20) struct zoned_traits { }; template <> (2)(since C++ 20) struct zoned_traits<const std::chrono::time_zone *>; The class zoned_traits provides a way to customize the behavior of the constructors of std::chrono::zoned_time with custom time zone pointer types. In particular, it allows such types to specify…
std::chrono::zoned_time<Duration,TimeZonePtr>::zoned_time – std::chrono::zoned_time<Duration,TimeZonePtr>::zoned_time Synopsis zoned_time(); (1)(since C++ 20) zoned_time(const std::chrono::sys_time<Duration> &st); (2)(since C++ 20) zoned_time(const zoned_time &other) = default; (3)(since C++ 20) template <class Duration2> (4)(since C++ 20) zoned_time(const std::chrono::zoned_time<Duration2, TimeZonePtr> &other); explicit zoned_time(TimeZonePtr z); (5)(since C++ 20) explicit zoned_time(std::string_view name); (6)(since C++ 20) zoned_time(TimeZonePtr z, const std::chrono::sys_time<Duration> &st); (7)(since C++ 20) zoned_time(std::string_view name, const…
std::chrono::year_month_weekday_last::year_month_weekday_last – std::chrono::year_month_weekday_last::year_month_weekday_last Synopsis constexpr year_month_weekday_last(const std::chrono::year &y, const std::chrono::month &m, (since C++ 20) const chrono::weekday_last &wdl) noexcept; Constructs a year_month_weekday_last object storing the year y, the month m, and the weekday wdl.weekday(). The constructed object represents the last weekday of that year and month. Notes A year_month_weekday_last can also be created by combining one…
std::chrono::year_month_weekday_last::year,std::chrono::year_month_weekday_last::month, – std::chrono::year_month_weekday_last::year,std::chrono::year_month_weekday_last::month, Synopsis std::chrono::year_month_weekday_last::weekday_last constexpr std::chrono::year year() const noexcept; (since C++20) constexpr std::chrono::month month() const noexcept; (since C++20) constexpr std::chrono::weekday weekday() const noexcept; (since C++20) constexpr std::chrono::weekday_last weekday_last() const noexcept; (since C++20) Retrieves the field values stored in this year_month_weekday_last object. Return values 1) Returns the stored std::chrono::year value. 2) Returns the stored std::chrono::month value. 3) Returns the stored std::chrono::weekday value. 4) std::chrono::weekday_last(weekday()).
std::chrono::year_month_weekday_last::operatorsys_days,std::chrono::year_month_weekday_last::operatorlocal_days – std::chrono::year_month_weekday_last::operatorsys_days,std::chrono::year_month_weekday_last::operatorlocal_days Synopsis constexpr operator std::chrono::sys_days() const noexcept; (1) (since C++20) explicit constexpr operator std::chrono::local_days() const noexcept; (2) (since C++20) Converts *this to a std::chrono::time_point representing the same date as this year_month_weekday_last. 1) If ok() is true, returns a sys_days that represents the last weekday() of the year() and month(). Otherwise, the returned value…
std::chrono::year_month_weekday_last::operator+=,std::chrono::year_month_weekday_last::operator-= – std::chrono::year_month_weekday_last::operator+=,std::chrono::year_month_weekday_last::operator-= Synopsis constexpr std::chrono::year_month_weekday_last &operator+=(const std::chrono::years &dy) const noexcept; (1)(since C++ 20) constexpr std::chrono::year_month_weekday_last & operator+=(const std::chrono::months &dm) const noexcept; (2)(since C++ 20) constexpr std::chrono::year_month_weekday_last & operator-=(const std::chrono::years &dy) const noexcept; (3)(since C++ 20) constexpr std::chrono::year_month_weekday_last & operator-=(const std::chrono::months &dm) const noexcept; (4) (since C++20) Modifies the time point *this represents by the…
std::chrono::year_month_weekday_last::ok – std::chrono::year_month_weekday_last::ok Synopsis constexpr bool ok() const noexcept; (since C++20) Checks if this object represents a valid date. Since a year_month_weekday_last represents the last weekday of a particular month, it is valid as long as the year, month and weekday are valid. Return value year().ok() && month().ok() && weekday().ok()
std::chrono::year_month_weekday_last – std::chrono::year_month_weekday_last Synopsis Defined in header <chrono> class year_month_weekday_last; (since C++20) The class year_month_weekday_last represents the last weekday of a specific year and month. It is a field-based time point, with a resolution of std::chrono::days, except that it is limited to pointing to the last weekday of a year and month. std::chrono::years- and std::chrono::months-oriented…
std::chrono::year_month_weekday::year_month_weekday – std::chrono::year_month_weekday::year_month_weekday Synopsis year_month_weekday() = default; (1)(since C++ 20) constexpr year_month_weekday(const std::chrono::year &y, const std::chrono::month &m, (2)(since C++ 20) const std::chrono::weekday_indexed &wdi) noexcept; constexpr year_month_weekday(const std::chrono::sys_days &dp) noexcept; (3)(since C++ 20) explicit constexpr year_month_weekday(const std::chrono::local_days &dp) noexcept; (4)(since C++ 20) Constructs a year_month_weekday object. 1) Default constructor leaves the fields uninitialized. 2) Constructs a…
std::chrono::year_month_weekday::year,std::chrono::year_month_weekday::month, – std::chrono::year_month_weekday::year,std::chrono::year_month_weekday::month, Synopsis std::chrono::year_month_weekday::weekday_indexed constexpr std::chrono::year year() const noexcept; (1)(since C++ 20) constexpr std::chrono::month month() const noexcept; (2)(since C++ 20) constexpr std::chrono::weekday weekday() const noexcept; (3)(since C++ 20) constexpr unsigned index() const noexcept; (4)(since C++ 20) constexpr std::chrono::weekday_indexed weekday_indexed() const(5)(since C++ 20) noexcept; Retrieves the field values stored in this year_month_weekday object. Return values…
std::chrono::year_month_weekday::operatorsys_days,std::chrono::year_month_weekday::operatorlocal_days – std::chrono::year_month_weekday::operatorsys_days,std::chrono::year_month_weekday::operatorlocal_days Synopsis constexpr operator std::chrono::sys_days() const noexcept; (1) (since C++20) explicit constexpr operator std::chrono::local_days() const noexcept; (2) (since C++20) Converts *this to a std::chrono::time_point representing the same date as this year_month_weekday. 1) If year().ok() && month().ok() && weekday().ok(): * If index() == 0, returns a sys_days that represents the date 7 days prior…
std::chrono::year_month_weekday::operator+=,std::chrono::year_month_weekday::operator-= – std::chrono::year_month_weekday::operator+=,std::chrono::year_month_weekday::operator-= Synopsis constexpr std::chrono::year_month_weekday &operator+=(const std::chrono::years &dy) const noexcept; (1)(since C++ 20) constexpr std::chrono::year_month_weekday & operator+=(const std::chrono::months &dm) const noexcept; (2)(since C++ 20) constexpr std::chrono::year_month_weekday & operator-=(const std::chrono::years &dy) const noexcept; (3)(since C++ 20) constexpr std::chrono::year_month_weekday & operator-=(const std::chrono::months &dm) const noexcept; (4) (since C++20) Modifies the time point *this represents by the…
std::chrono::year_month_weekday::ok – std::chrono::year_month_weekday::ok Synopsis constexpr bool ok() const noexcept; (since C++20) Checks if this year_month_weekday object represents a valid date. Return value true if this year_month_weekday object represents a valid date, that is, year().ok() && month().ok() && weekday_indexed().ok() is true and there are at least index() weekday()s in the specified year and month. Otherwise false.
std::chrono::year_month_weekday – std::chrono::year_month_weekday Synopsis Defined in header <chrono> class year_month_weekday; (since C++20) The class year_month_weekday represents the n-th weekday of a specific year and month. It is a field-based time point, with a resolution of std::chrono::days. std::chrono::years- and std::chrono::months-oriented arithmetic are supported directly. An implicit conversion to and from std::chrono::sys_days allows std::chrono::days-oriented arithmetic to be…
std::chrono::year_month_day_last::year_month_day_last – std::chrono::year_month_day_last::year_month_day_last Synopsis constexpr year_month_day_last(const std::chrono::year &y, (since C++ 20) const std::chrono::month_day_last &mdl) noexcept; Constructs a year_month_day_last object storing the year y and the month mdl.month(). The constructed object represents the last day of that year and month. Notes A year_month_day_last can also be created by combining a std::chrono::year_month with std::chrono::last using operator/. See…
std::chrono::year_month_day_last::year,std::chrono::year_month_day_last::month,std::chrono::year_month_day_last::day,std::chrono::year_month_day_last::month_day_last – std::chrono::year_month_day_last::year,std::chrono::year_month_day_last::month,std::chrono::year_month_day_last::day,std::chrono::year_month_day_last::month_day_last Synopsis constexpr std::chrono::year year() const noexcept; (1) (since C++20) constexpr std::chrono::month month() const noexcept; (2) (since C++20) constexpr std::chrono::day day() const noexcept; (3) (since C++20) constexpr std::chrono::month_day_last month_day_last() const noexcept; (4) (since C++20) Retrieves the field values stored in this year_month_day_last object. Return values 1) Returns the stored std::chrono::year value. 2) Returns…