std::chrono::operator<<(std::chrono::year)

 

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Symbols index

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Date and time library

Time point time_point (C++11) clock_time_conversion (C++20)   clock_cast (C++20) Duration duration (C++11) Clocks system_clock (C++11) steady_clock (C++11) is_clock (C++20) utc_clock (C++20) tai_clock (C++20) high_resolution_clock (C++11) gps_clock (C++20) file_clock (C++20) local_t (C++20) Time of day is_amis_pm (C++20)(C++20) make12make24 (C++20)(C++20) hh_mm_ss (C++20)

Calendar day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)   weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20) last_speclast (C++20)(C++20) chrono I/O parse (C++20)

Time zone tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20) sys_info (C++20) local_info (C++20) nonexistent_local_time (C++20) ambiguous_local_time (C++20) locate_zone (C++20) current_zone (C++20) time_zone (C++20) choose (C++20) zoned_traits (C++20) zoned_time (C++20) time_zone_link (C++20) leap_second (C++20) leap_second_info (C++20) get_leap_second_info (C++20) C-style date and time

 

std::chrono::year

Member functions

year::year

year::operator++year::operator--

year::operator+=year::operator-=

year::operator+year::operator-

year::is_leap

year::operator int

year::ok

year::min

year::max

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

operator""y

Helper classes

formatter<std::chrono::year>

hash<std::chrono::year> (C++26)

 

Defined in header <chrono>
template< class CharT, class Traits > std::basic_ostream<CharT, Traits>& operator<<( std::basic_ostream<CharT, Traits>& os, const std::chrono::year& y );		(since C++20)

Forms a std::basic_string<CharT> s consisting of the year value stored in y formatted as a decimal number, left-padded with 0 to four digits if the result would otherwise be less than four digits. Then, if !y.ok(), append " is not a valid year" to the formatted string. Inserts that string into os.

Equivalent to

return os << (y.ok() ? std::format(STATICALLY_WIDEN<CharT>("{:%Y}"), y) : std::format(STATICALLY_WIDEN<CharT>("{:%Y} is not a valid year"), y));

where STATICALLY_WIDEN<CharT>("...") is "..." if CharT is char, and L"..." if CharT is wchar_t.

Return value

os

Example

Run this code

#include <chrono>
#include <iostream>
 
int main()
{
    constexpr std::chrono::year y1{2020}, y2{-020}, y3{98304};
    std::cout << y1 << '\n'
              << y2 << '\n'
              << y3 << '\n';
}

Possible output:

2020
-0016
-32768 is not a valid year

See also

format (C++20)	stores formatted representation of the arguments in a new string (function template)
std::formatter<std::chrono::year> (C++20)	formatting support for year (class template specialization)