std::chrono..._month_day)(3)

🌸 NAME 🌸

std::chrono::operator<<(std::chrono::year_month_day) - std::chrono::operator<<(std::chrono::year_month_day)

okay bestie, this is the std::chrono..._month_day)(3) page from the C++ Standard Libary manual (yes, “Libary” is literally how it’s spelled up top, no cap 💅). It’s all about streaming a std::chrono::year_month_day and making it look cute as text.

✨ Synopsis ✨

Defined in header <chrono>:

template< class CharT, class Traits >

std::basic_ostream<CharT, Traits>&
operator<<( std::basic_ostream<CharT, Traits>& os,
            const std::chrono::year_month_day& ymd );

(since C++20)

Outputs a textual representation of ymd into the stream os. This first forms a std::basic_string<CharT> s consisting of a textual representation of the date in the format yyyy-mm-dd (same as the one output by formatter with the %F specifier). Then, if !ymd.ok(), appends " is not a valid date" to s. Inserts s into os.

Equivalent to

return os << (ymd.ok() ?
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:%F}"), ymd) :
    std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:%F} is not a valid date"),
ymd));

where STATICALLY_WIDEN<CharT>("...") is "..." if CharT is char, and L"..." if CharT is wchar_t.

🫶 Return value 🫶

os

🧚 Example 🧚

This section is incomplete

Reason: no example

👀 See also 👀

• format (C++20) — stores formatted representation of the arguments in a new string (function template)
• std::formatter<std::chrono::year_month_day> (C++20) — formatting support for year_month_day (class template specialization)

🏷️ Category 🏷️

• Todo no example

xoxo, your C++ Standard Libary bestie 💖 — source/version/date: http://cppreference.com, 2024.06.10.