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

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< cpp‎ | chrono‎ | weekday indexed
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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

(C++20)
 stores formatted representation of the arguments in a new string
(function template)
(C++20)
 formatting support for weekday
(class template specialization)
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