Re: [Boost-users] Limitations of BOOST_COROUTINES_V2 (pass by reference)

Subject: Re: [Boost-users] Limitations of BOOST_COROUTINES_V2 (pass by reference)
From: TONGARI J (tongari95_at_[hidden])
Date: 2014-07-04 11:12:46

2014-07-04 22:27 GMT+08:00 Nat Goodspeed <nat_at_[hidden]>:

> On Fri, Jul 4, 2014 at 2:28 AM, Mueller-Roemer, Johannes Sebastian
> <Johannes.Sebastian.Mueller-Roemer_at_[hidden]> wrote:
>
> > Sorry for the misunderstanding, the part in the parentheses was meant to
> point out that I currently do not require bidirectional data flow, so I
> don't have a use case for that ;)
>
> I do understand that. My question was directed more to the mailing
> list in general. I'm content with unidrectional coroutine data flow
> until someone surfaces a compelling use case for bidirectional.
>
> > The auto& is not the issue and works just fine in the
> BOOST_COROUTINES_V1 case (and if it were, it would be a compiler bug as
> auto& must match std::string const &).
>
> Could it be a compiler bug anyway? The following works fine with gcc 4.2:
>
> #include <boost/coroutine/all.hpp>
> #include <iostream>
>
> void coro_fn(boost::coroutines::coroutine<const std::string&>::push_type&
> sink)
> {
>     sink("Hello world!\n");
> }
>
> int main(int argc, char *argv[])
> {
>     boost::coroutines::coroutine<const std::string&>::pull_type
> coro(coro_fn);
>     std::cout << coro.get() << std::endl;
>     return 0;
> }
>

Call coro() and you'll see the error.
Seems that the specializations of pull_coroutine_base
and pull_coroutine_object for R& is unnecessary and erroneous.