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

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Utilities library
General utilities
Date and time
Function objects
Formatting library (C++20)
(C++11)
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
(C++20)
Swap and type operations
(C++14)
(C++11)
(C++11)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++17)
(C++23)
Elementary string conversions
(C++17)
(C++17)
 
 
 
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)
specialization of std::formatter that formats a weekday according to the provided format
(class template specialization)