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

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std::chrono::duration
Member functions
duration::operator+= duration::operator-= duration::operator*= duration::operator/= duration::operator%=

Non-member functions
Helper classes
(1)
duration & operator + = ( const duration & d ) ;
(since C++11)
(constexpr since C++17)
(2)
duration & operator - = ( const duration & d ) ;
(since C++11)
(constexpr since C++17)
(3)
duration & operator * = ( const rep & rhs ) ;
(since C++11)
(constexpr since C++17)
(4)
duration & operator / = ( const rep & rhs ) ;
(since C++11)
(constexpr since C++17)
(5)
duration & operator % = ( const rep & rhs ) ;
(since C++11)
(constexpr since C++17)
(6)
duration & operator % = ( const duration & rhs ) ;
(since C++11)
(constexpr 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

Run this code 
#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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