What are some examples of coroutines in C++?

Can you explain what coroutines are in C++?

Coroutines in C++ are a generalization of subroutines that allow you to pause and resume execution, enabling asynchronous programming.

Can you provide some examples of how to use coroutines?

Sure! Here's a simple example:

#include <coroutine>
#include <iostream>

struct Generator {
    struct promise_type {
        int current_value;
        auto get_return_object() { return Generator{this}; }
        auto initial_suspend() { return std::suspend_always{}; }
        auto final_suspend() noexcept { return std::suspend_always{}; }
        void unhandled_exception() { std::exit(1); }
        auto yield_value(int value) {
            current_value = value;
            return std::suspend_always{};
        }
        void return_void() {}
    };

    promise_type* promise;
    Generator(promise_type* p) : promise(p) {}
    int get() { return promise->current_value; }
};

Generator count() {
    for (int i = 0; i < 5; ++i) {
        co_yield i;
    }
}

int main() {
    auto gen = count();
    for (int i = 0; i < 5; ++i) {
        std::cout << gen.get() << std::endl;
    }
}

This example creates a generator that yields numbers from 0 to 4.

What are the benefits of using coroutines?

Coroutines simplify asynchronous programming by allowing you to write code that looks synchronous, making it easier to read and maintain.