std::chrono::operator<<(std::chrono::weekday)

 

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std::chrono::weekday

Member functions

weekday::weekday

weekday::operator++weekday::operator--

weekday::operator+=weekday::operator-=

weekday::c_encodingweekday::iso_encoding

weekday::ok

weekday::operator[]

Nonmember functions

operator==

operator+operator-

operator<<

from_stream

Helper classes

formatter<std::chrono::weekday>

formatter<std::chrono::hash> (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::weekday& wd );		(since C++20)

If !wd.ok(), inserts wd.c_encoding() followed by " is not a valid weekday" into os. Otherwise, forms a std::basic_string<CharT> s consisting of the abbreviated weekday name for the weekday represented by wd, determined using the locale associated with os, and inserts s into os.

Equivalent to

return os << (wd.ok() ?
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:L%a}"), wd) :
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{} is not a valid weekday"),
                wd.c_encoding()));

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

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

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