std::chrono::operator<< (std::chrono::year_month_day)

 

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C-style date and time

 

std::chrono::year_month_day

Member functions

year_month_day::year_month_day

year_month_day::operator+=year_month_day::operator-=

year_month_day::yearyear_month_day::monthyear_month_day::day

year_month_day::operator sys_daysyear_month_day::operator local_days

year_month_day::ok

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

Helper classes

formatter<std::chrono::year_month_day>

 

template< class CharT, class Traits > std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const std::chrono::year_month_day& ymd);		(since C++20)

Outputs a textual representation of ymd into the stream os. This first forms a std::basic_string<CharT> s consisting of a textual representation of the date in the format yyyy-mm-dd (same as the one output by formatter with the %F specifier). Then, if !ymd.ok(), appends " is not a valid date" to s. Inserts s into os.

Equivalent to

return os << (ymd.ok() ?
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:%F}"), ymd) :
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:%F} is not a valid date"), ymd));

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

Return value

os.

See also

format (C++20)	stores formatted representation of the arguments in a new string (function template)
std::formatter<std::chrono::year_month_day>	specialization of std::formatter that formats a year_month_day according to the provided format (class template specialization)