std::chrono::year_month_day_last::ok

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Utilities library
General utilities
Date and time
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Formatting library (C++20)
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Relational operators (deprecated in C++20)
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(C++23)
Elementary string conversions
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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()

Example

#include <iostream>
#include <chrono>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto ymdl {std::chrono::last/11/2020};
    std::cout << (ymdl.ok()) << ' ';
    ymdl = std::chrono::year(2020)/std::chrono::month(13)/std::chrono::last;
    std::cout << (ymdl.ok()) << '\n';
}

Output:

true false