async_generator.h File Reference

Asynchronous generator. More...

#include <coroutine>
#include <exception>
#include <iterator>
#include <memory>
#include <type_traits>
#include <utility>
#include "detail.h"
#include "exceptions.h"

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Classes
class	wwa::coro::async_generator< Result >
	An asynchronous generator that produces values of type Result. More...
class	wwa::coro::async_generator< Result >::iterator
	An input iterator that asynchronously produces values of type Result. More...
class	wwa::coro::async_generator< Result >::promise_type
	The promise type of the generator. More...

Namespaces
namespace	wwa
namespace	wwa::coro
	Library namespace.

Detailed Description

Asynchronous generator.

This file contains the definition of an asynchronous generator class template. The async_generator template class allows for the creation of coroutine-based generators that produce values of a specified type asynchronously. It provides an interface for iterating over the generated values using co_await and asynchronous iteration.

Example usage:

wwa::coro::async_generator<int> async_first_n(int n)
{
    int v = 0;
    while (v < n) {
        co_yield v;
        // Asynchronous generators can use `co_await`; synchronous ones cannot
        v = co_await get_next_value(v);
    }
}

auto gen = async_first_n(5);
auto it  = co_await gen.begin();  // IMPORTANT! co_await is required
auto end = gen.end();
 
while (it != end) {
    std::cout << *it << "\n";
    co_await ++it;  // IMPORTANT! co_await is required
}

With the help of sync_generator_adapter, you can adapt an asynchronous generator to use it in a synchronous context (e.g., range-based for loops or views).

Definition in file async_generator.h.