std::chrono::operator<<(std::chrono::weekday_indexed)

 

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std::chrono::weekday_indexed

Member functions

weekday_indexed::weekday_indexed

weekday_indexed::weekday

weekday_indexed::index

weekday_indexed::ok

Nonmember functions

operator==

operator<<

Helper classes

formatter<std::chrono::weekday_indexed>

 

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_indexed& wdi );		(since C++20)

Outputs a textual representation of wdi into the stream os, as if by:

if (wdi.index() >=1 && wdi.index() <= 5) {
    os << std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:L}[{}]"),
                      wdi.weekday(), wdi.index());
} else {
    os << std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:L}[{} is not a valid index]"),
                      wdi.weekday(), wdi.index());
}

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)	specialization of std::formatter that formats a weekday according to the provided format (class template specialization)