std::chrono...o::duration)(3)

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

Hey bestie! You're reading the std::chrono::abs(std::chrono::duration) page from the C++ Standard Libary manual. Yes, that's the manual name, and yes, we're keeping it exactly like that. 💅

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🌸 NAME 🌸

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

(The page literally names it twice, so I'm literally naming it twice. Iconic behavior. 🫶)

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✨ Synopsis ✨

Defined in header <chrono>:

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

C++17 girlies, this one's for you. 💜

Okay so what does it do? It returns the absolute value of the duration d. Specifically: if d >= d.zero(), return d; otherwise return -d. That's the whole vibe check. ✨

Heads up though, because this part matters: the function does not participate in overload resolution unless std::numeric_limits<Rep>::is_signed is true. That's a hard requirement, no cap. 🔥

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🎀 Parameters 🎀

• d — duration

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🦋 Return value 🦋

Absolute value of d. Slay. 💖

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👑 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;
}

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🌈 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

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👀 See also 👀

• operator+ — implements unary + and unary -
• operator- — (public member function)
• abs(int)
• labs — computes absolute value of an integral value (\(\small{|x|}\)|x|) (function)
• llabs — (function) (C++11)

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That's the whole page, bestie! Big kiss from the C++ Standard Libary crew 💋 — source: http://cppreference.com, version: 2024.06.10, and date: 2024.06.10. The footer title ting was std::chrono...o::duration)(3), mwah! 💖🎀🦋