std::chrono::year::operator+=, std::chrono::year::operator-=

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< cpp‎ | chrono‎ | year
 
 
Utilities library
General utilities
Date and time
Function objects
Formatting library (C++20)
(C++11)
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
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constexpr std::chrono::year& operator+=( const std::chrono::years& y ) noexcept;
(1) (since C++20)
constexpr std::chrono::year& operator-=( const std::chrono::years& y ) noexcept;
(2) (since C++20)

Adds or subtracts y.count() years from the year value.

1) Equivalent to *this = *this + y;
2) Equivalent to *this = *this - y;

Return value

A reference to this year after modification.

Notes

If the result would be outside the range [-32767, 32767], the actual stored value is unspecified.

Example

#include <iostream>
#include <chrono>
 
int main()
{
    using namespace std::literals::chrono_literals;
    std::cout << std::boolalpha;
 
    std::chrono::year y {2020};
 
    y += std::chrono::years(12);
    std::cout << (y == 2032y) << ' ';
 
    y -= std::chrono::years(33);
    std::cout << (y == 1999y) << '\n';
}

Output:

true true

See also

increments or decrements the year
(public member function)
performs arithmetic on years
(function)