std::chrono::operator<<(std::chrono::year_month)
From cppreference.com
                    
                                        
                    < cpp | chrono | year month
                    
                                                            
                    | Defined in header  <chrono> | ||
| template< class CharT, class Traits > std::basic_ostream<CharT, Traits>& | (since C++20) | |
Outputs a textual representation of ym into the stream os, as if by
os << std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{}/{:L}"), ym.year(), ym.month())
where STATICALLY_WIDEN<CharT>("{}/{:L}") is "{}/{:L}" if CharT is char, and L"{}/{:L}" if CharT is wchar_t.
Return value
os.
Example
| This section is incomplete Reason: no example | 
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 | Lis needed to use the given locale | 
See also
| (C++20) | stores formatted representation of the arguments in a new string (function template) | 
| formatting support for year_month(class template specialization) |