std::chrono::year_month_day_last::ok

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Date and time utilities
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Clocks
(C++20)
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Calendars
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Time zones
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C-style date and time
constexpr bool ok() const noexcept;
(since C++20)

Checks if *this represents a valid date. Because a year_month_day_last represents the last day of a particular month, it represents a valid date as long as the year and month are valid.

Return value

year().ok() && month().ok()