std::litera...perator""min(3)

💖 NAME 💖

Okay bestie, this is the std::litera...perator""min(3) page from the C++ Standard Libary manual, and it's literally about std::literals::chrono_literals::operator""min — yes, that whole gorgeous name again: std::literals::chrono_literals::operator""min. 🫶

✨ Synopsis ✨

Two overloads, both (since C++14) — here's the exact synopsis, no cap:

Defined in header <chrono>
constexpr chrono::minutes                                (1) (since C++14)
    operator""min( unsigned long long mins );
constexpr chrono::duration</*unspecified*/, ratio<60,1>> (2) (since C++14)
    operator""min( long double mins );

This forms a std::chrono::duration literal representing minutes. Periodt. 💅

1. Integer literal — returns exactly std::chrono::minutes(mins).
2. Floating-point literal — returns a floating-point duration equivalent to std::chrono::minutes.

🌸 Parameters 🌸

• mins — the number of minutes. 🎀

👑 Return value 👑

The std::chrono::duration literal. That's it, that's the return value. ✨

🛠️ Possible implementation 🛠️

constexpr std::chrono::minutes operator""min(unsigned long long m)
{
    return std::chrono::minutes(m);
}
constexpr std::chrono::duration<long double,
                                std::ratio<60,1>> operator""min(long double m)
{
    return std::chrono::duration<long double, ratio<60,1>> (m);
}

🦋 Notes 🦋

Okay so this operator is declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are inline namespaces. Access to this operator can be gained with:

• using namespace std::literals,
• using namespace std::chrono_literals, or
• using namespace std::literals::chrono_literals.

In addition, within the namespace std::chrono, the directive using namespace literals::chrono_literals; is provided by the standard library, so that if a programmer uses using namespace std::chrono; to gain access to the classes in the chrono library, the corresponding literal operators become visible as well. iykyk ✨

🌈 Example 🌈

// Run this code

#include <chrono>
#include <iostream>

int main()
{
    using namespace std::chrono_literals;
    auto lesson = 45min;
    auto halfmin = 0.5min;
    std::cout << "One lesson is " << lesson.count() << " minutes"
                 " (" << lesson << ")\n"
              << "Half a minute is " << halfmin.count() << " minutes"
                 " (" << halfmin << ")\n";
}

📤 Output: 📤

One lesson is 45 minutes (45min)
Half a minute is 0.5 minutes (0.5min)

🎀 See also 🎀

• constructor — constructs new duration (public member function of std::chrono::duration<Rep,Period>)

Bye bestie! 💋 This page came from http://cppreference.com, version/date 2024.06.10, and the footer source/version/date wraps it all up with std::litera...perator""min(3). Slay. 🌟