# std::chrono::operator<<(std::chrono::month_day)

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< cpp‎ | chrono‎ | month day

Defined in header `<chrono>` |  |
template< class CharT, class Traits > std::basic_ostream<CharT, Traits>& operator<<( std::basic_ostream<CharT, Traits>& os, const std::chrono::month_day& md ); |  | (since C++20)

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

os << std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:L}/{}"), md.month(), md.day())

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 | `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::month_day> (C++20) | formatting support for `month_day` (class template specialization)

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