< cpp‎ | chrono
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Defined in header <chrono>
constexpr std::chrono::year operator""y( unsigned long long y ) noexcept;
(since C++20)

Forms a std::chrono::year literal representing a year in the proleptic Gregorian calendar.


[edit] Parameters

y - the year value

[edit] Return value

A std::chrono::year initialized from int(y). If y is not in the range [-3276732767], the stored value is unspecified.

[edit] Possible implementation

constexpr std::chrono::year operator""y(unsigned long long y) noexcept
    return std::chrono::year(static_cast<int>(y));

[edit] Notes

This operator is declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are inline namespaces. Access to this operator can be gained with:

  • using namespace std::literals,
  • using namespace std::chrono_literals, or
  • using namespace std::literals::chrono_literals.

In addition, within the namespace std::chrono, the directive using namespace literals::chrono_literals; is provided by the standard library, so that if a programmer uses using namespace std::chrono; to gain access to the classes in the chrono library, the corresponding literal operators become visible as well.

[edit] Example

#include <chrono>
#include <iostream>
int main()
    using namespace std::literals;
    std::cout << int(2020y)  << '\t' << 2020y  << '\n'
              << int(-220y)  << '\t' << -220y  << '\n'
              << int(3000y)  << '\t' << 3000y  << '\n'
              << int(32768y) << '\t' << 32768y << '\n'  // unspecified
              << int(65578y) << '\t' << 65578y << '\n'; // unspecified

Possible output:

2020	2020
-220	-0220
3000	3000
-32768	-32768 is not a valid year
42	0042

[edit] See also

constructs a year
(public member function of std::chrono::year) [edit]