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std::chrono::day:: ok

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< cpp ‎ | chrono ‎ | day
C++
Date and time library
std::chrono::day
constexpr bool ok ( ) const noexcept ;
(since C++20)

Checks if the day value stored in * this is in the valid range, i.e., [ 1 , 31 ] .

Return value

true if the day value stored in * this is in the range [ 1 , 31 ] . Otherwise false .

Example

Run this code 
#include <chrono>
using namespace std::chrono_literals;
constexpr std::chrono::day d0{00};
constexpr std::chrono::day d1{13};
constexpr std::chrono::day d2{42};
static_assert
(
    d0 == 0d && !d0.ok() &&
    d1 == 13d && d1.ok() &&
    d2 == 42d && !d2.ok()
);
int main() {}

See also

retrieves the stored day value
(public member function)