std::chrono::duration::operator+=, -=, *=, /=, %=

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)
Dynamic memory management
Error handling
Program utilities
Variadic functions
Library feature-test macros
Date and time
Function objects
initializer_list (C++11)
bitset
hash (C++11)
integer_sequence (C++14)
Relational operators (deprecated in C++20)
rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=
Comparisons (C++20)
strong_order weak_order partial_order strong_equal weak_equal	strong_ordering weak_ordering partial_ordering strong_equality weak_equality	is_eqis_neqis_ltis_lteqis_gtis_gteq
common_comparison_category
Common vocabulary types
pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
Swap, forward and move
swap
exchange (C++14)
forward (C++11)
move (C++11)
move_if_noexcept (C++11)
Elementary string conversions
to_chars (C++17)
from_chars (C++17)
chars_format (C++17)
Type operations
declval (C++11)
as_const (C++17)
launder (C++17)

 

Date and time utilities

duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
Clocks
system_clock (C++11) steady_clock (C++11) high_resolution_clock (C++11) is_clock (C++20)	utc_clock (C++20) tai_clock (C++20) gps_clock (C++20) file_clock (C++20) local_t (C++20)
Calendars
day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20) year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)	weekday_indexed (C++20) weekday_last (C++20) month_day (C++20) month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20)
Time zones
tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20)	time_zone (C++20) locate_zone (C++20) current_zone (C++20) zoned_time (C++20) link (C++20) leap (C++20)
C-style date and time

 

std::chrono::duration

Member functions
duration::duration
duration::operator=
duration::count
duration::zero
duration::min
duration::max
duration::operator+duration::operator-
duration::operator++duration::operator--
duration::operator+=duration::operator-=duration::operator*=duration::operator/=duration::operator%=
Non-member functions
operator+operator-operator*operator/operator% operator==operator!=operator<operator<=operator>operator>= operator<< (C++20) to_stream (C++20)	common_type duration_cast floor (C++17) ceil (C++17) round (C++17) abs (C++17) operator""h (C++14) operator""min (C++14) operator""s (C++14) operator""ms (C++14) operator""us (C++14) operator""ns (C++14) from_stream (C++20)
Helper classes
treat_as_floating_point duration_values

 

	(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

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

operator++operator++(int)operator--operator--(int)	increments or decrements the tick count (public member function)
operator+operator-operator*operator/operator%	implements arithmetic operations with durations as arguments (function template)