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std::chrono::operator<<(std::chrono::sys_time)

Defined in header <chrono> 
template< class CharT, class Traits, class Duration >
std::basic_ostream<CharT, Traits>&
    operator<<( std::basic_ostream<CharT, Traits>& os,
                const std::chrono::sys_time<Duration>& tp );
 (1) (since C++20) 
template< class CharT, class Traits, class Duration >
std::basic_ostream<CharT, Traits>&
    operator<<( std::basic_ostream<CharT, Traits>& os,
                const std::chrono::sys_days& tp );
 (2) (since C++20)

Outputs tp into the stream os.

1) Equivalent to: 
return os << std::format(os.getloc(), STATICALLY-WIDEN<CharT>("{:L%F %T}"), tp);

where STATICALLY_WIDEN<CharT>("{:L%F %T}") is "{:L%F %T}" if CharT is char, and L"{:L%F %T}" if CharT is wchar_t.
This overload participates in overload resolution only if std::chrono::treat_as_floating_point_v<typename Duration::rep> is false and Duration(1) < std::chrono::days(1).

2) Equivalent to os << std::chrono::year_month_day(tp);.

Return value

os

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
P2372R3 C++20 the given locale was used by default L is needed to use the given locale

See also

(C++20)
formatting support for sys_time
(class template specialization)
(C++20)
stores formatted representation of the arguments in a new string
(function template)
(C++20)
outputs a year_month_day into a stream
(function template)

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