[#async_for]
== cobalt/async_for.hpp

For types like generators a `BOOST_COBALT_FOR` macro is provided, to emulate an `for co_await` loop.


[source,cpp]
----
cobalt::generator<int> gen();

cobalt::main co_main(int argc, char * argv[])
{
    BOOST_COBALT_FOR(auto i, gen())
        printf("Generated value %d\n", i);

    co_return 0;
}

----

The requirement is that the <<awaitable,awaitable>> used in the for loop has an `operator bool` to check if it
can be awaited again. This is the case for <<generator, generator>> and <<promise,promise>>.