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std::chrono::duration<Rep,Period>::operator+=, -=, *=, /=, %=

(1) 
duration& operator+=(const duration& d);
 (until C++17) 
constexpr duration& operator+=(const duration& d);
 (since C++17)
(2) 
duration& operator-=(const duration& d);
 (until C++17) 
constexpr duration& operator-=(const duration& d);
 (since C++17)
(3) 
duration& operator*=(const rep& rhs);
 (until C++17) 
constexpr duration& operator*=(const rep& rhs);
 (since C++17)
(4) 
duration& operator/=(const rep& rhs);
 (until C++17) 
constexpr duration& operator/=(const rep& rhs);
 (since C++17)
(5) 
duration& operator%=(const rep& rhs);
 (until C++17) 
constexpr duration& operator%=(const rep& rhs);
 (since C++17)
(6) 
duration& operator%=(const duration& rhs);
 (until C++17) 
constexpr duration& operator%=(const duration& rhs);
 (since C++17)

Performs compound assignments between two durations with the same period or between a duration and a tick count value.

If rep_ is the member variable holding the number of ticks in this duration object,

1) Equivalent to rep_ += d.count(); return *this;
2) Equivalent to rep_ -= d.count(); return *this;
3) Equivalent to rep_ *= rhs; return *this;
4) Equivalent to rep_ /= rhs; return *this;
5) Equivalent to rep_ %= rhs; return *this;
6) Equivalent to rep_ %= d.count(); return *this;

Parameters

d - duration on the right-hand side of the operator
rhs - number of ticks on the right-hand side of the operator

Return value

A reference to this duration after modification.

Example

#include <chrono>
#include <iostream>
 
int main()
{
    std::chrono::minutes m(11);
    m *= 2;
    m += std::chrono::hours(10); // hours implicitly convert to minutes
    std::cout << m.count() << " minutes equals "
              << std::chrono::duration_cast<std::chrono::hours>(m).count() 
              << " hours and ";
    m %= std::chrono::hours(1);
    std::cout << m.count() << " minutes\n";
}

Output:

622 minutes equals 10 hours and 22 minutes

See also

increments or decrements the tick count
(public member function)
(C++11)
 implements arithmetic operations with durations as arguments
(function template)

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