status changed; resolution set

olli — Sat, 25 Apr 2015 15:20:53 GMT

status new → closed
resolution → wontfix

const_iterator must not be defined - it will never be const because each incrementation will modify/changed the associated coroutine. removing the declaration for const_iteration from the header will not help.

kozlov.taras@… — Mon, 27 Apr 2015 09:37:12 GMT

First of all boost coroutines and ranges can't be used together at the moment. This is definitly a bug. And ok, probably it should be fixed in Boost.Range

I want to clearify problem again. Using generator together with ANY non mutating Boost.Range algorithm yields compiler error

Example

asymmetric_coroutine<int>::pull_type make_dummy_range()
{
    return asymmetric_coroutine<int>::pull_type([](asymmetric_coroutine<int>::push_type& yield)
    {
        yield(1);
    });
}
int _tmain(int argc, _TCHAR* argv[])
{
    boost::for_each(make_dummy_range(), ...); //error
    boost::max_element(make_dummy_range()); //error
    boost::distance(make_dummy_range()); //error
    boost::find(make_dummy_range(), 1); //error
}

I put this bug to boost.coroutines for two reasons.

It is known problem that SinglePassRange can't define perfect const_iterator, but it is also common and convinient workaround to override range_const_iterator to return mutable iterator. So any algorithm which accept const Range& can work with it.

Coroutines in Boost 1.55 already provided const_iterator, so Boost 1.58 just broken some existing code.

olli — Wed, 29 Apr 2015 18:34:58 GMT

commit pushed to branch develop

Boost C++ Libraries: Ticket #11234: boost::asymmetric_coroutine doesn't compile when used with boost::range::algorithms

status changed; resolution set