"vicente.botet" <vicente.botet@wanadoo.fr> writes:
----- Original Message ----- From: "Anthony Williams" <anthony.ajw@gmail.com> To: <boost@lists.boost.org> Sent: Monday, January 05, 2009 12:49 PM Subject: Re: [boost] [future William proposal] packaged_task do notacceptboost::ref of a nullary functor
"vicente.botet" <vicente.botet@wanadoo.fr> writes:
From: "vicente.botet" <vicente.botet@wanadoo.fr>
packaged_task do not accept boost::ref to nullary functions while thread allows it. Shouldn't packaged_task > accept them? How can the user workaround this issue? How thread solved this issue?
I have found a workaround. Instead of boost::packaged_task<unsigned > tsk(boost::ref(f)); I use boost::packaged_task<unsigned> tsk(boost::bind(boost::ref(f)));
Is this the correct way?
That's essentially what Boost.Thread does.
Given the prototypes: template<typename F> explicit thread(F func);
template <class F> explicit packaged_task(F const& f):
Shouldn't the prototype of packaged_task be template <class F> explicit packaged_task(F f):
Shouldn't boost::thread(boost::ref(f)); fail or boost::packaged_task<unsigned> tsk(boost::ref(f)); succeed?
What is the reason to make them different?
Hmm. I'm not sure what the difference is with a plain ref(f). Boost.thread uses bind<void>(f,args) when you specify args in the constructor, but doesn't do anything for a plain function. I don't know why it wouldn't work with packaged_task, but I haven't tried it. I'll investigate. Anthony -- Anthony Williams Author of C++ Concurrency in Action | http://www.manning.com/williams Custom Software Development | http://www.justsoftwaresolutions.co.uk Just Software Solutions Ltd, Registered in England, Company Number 5478976. Registered Office: 15 Carrallack Mews, St Just, Cornwall, TR19 7UL, UK