std::chrono::operator<< (std::chrono::year_month_day_last)
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                    < cpp | chrono | year month day last
                    
                                                            
                    | template <class CharT, class Traits> std::basic_ostream<CharT, Traits>& | (since C++20) | |
Outputs a textual representation of ymdl into os, as if by os << ymdl.year() << '/' << ymdl.month_day_last();
Return value
os.
Notes
This operator<< is primarily intended for debugging use. When used with non-default stream flags, the output may be surprising: