std::chrono::year_month_weekday::ok

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Date and time utilities
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Clocks
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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 year_month_weekday object represents a valid date.

Return value

true if this year_month_weekday object represents a valid date, that is, year().ok() && month().ok() && weekday_indexed().ok() is true and there are at least index() weekday()s in the specified year and month. Otherwise false.