std::chrono:: abs (std::chrono::duration)

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Defined in header <chrono>
template < class Rep, class Period >
constexpr std:: chrono :: duration < Rep, Period > abs ( std:: chrono :: duration < Rep, Period > d ) ;
(since C++17)

Returns the absolute value of the duration d . Specifically, if d >= d. zero ( ) , return d , otherwise return - d .

The function does not participate in the overload resolution unless std:: numeric_limits < Rep > :: is_signed is true .

Parameters

d - duration

Return value

Absolute value of d .

Possible implementation 

template<class Rep, class Period,
    class = std::enable_if_t<std::numeric_limits<Rep>::is_signed>>
constexpr std::chrono::duration<Rep, Period> abs(std::chrono::duration<Rep, Period> d)
{
    return d >= d.zero() ? +d : -d;
}

Example

Run this code 
#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono;
 
    static_assert(abs(-42s) == std::chrono::abs(42s));
 
    std::cout << "abs(+3min) = " << abs(3min).count() << '\n'
              << "abs(-3min) = " << abs(-3min).count() << '\n';
}

Output: 

abs(+3min) = 3
abs(-3min) = 3

See also

implements unary + and unary -
(public member function)
(C++11)
computes absolute value of an integral value ( |x| )
(function)
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