Re: [luabind] weak_ref issue patch

[Glen F. <hol...@gm...>]

Okay, thanks.  I wasn't 100% sure where you meant I should put this code -- i.e. where you call your bindLuaPart().  In the wrapper object's constructor?

What I tried is this: when I add a new object (wherever it comes from) to my C++ container, I run a method based on your code below -- if the object being added to my C++ container is based on the Lua wrapper class (tested using dynamic_cast), then I get its luabind wrapped_self_t and set its "strong ref" as in your code.

This seems to work, thanks!  I hope this "fix" (hack?) remains more or less valid for future updates to luabind (if there ever are any ;-).

Can you explain what this is doing?  I guess it just creates a strong reference to the Lua object, so it doesn't get garbage collected?  Do I need to do anything specific if the C++ object gets deleted (e.g. in its destructor), to release this strong reference to the Lua-side object?  Should I create a matching function, that calls reset() on its m_strong_ref?

Thanks,
Glen.

On Jul 23, 2013, at 12:20 PM, Christian <neu...@ya...> wrote:

> On Tuesday 23 July 2013, at 12:00:29, Glen Fraser <hol...@gm...> wrote:
>>> The struct name "only_accepts_nonconst_pointers" is meant as an error
>>> message: adopt only works with non-const pointers (meaning that the
>>> adopted type must be both a pointer and a non-const one).
>> 
>> Thanks, Christian -- I saw that, but I don't know how to fix it.  Presumably
>> this is related to the fact that the object I'm trying to "adopt" is held
>> in a smart pointer (boost::shared_ptr).  But I haven't declared the
>> smart_ptr as const anywhere…
>> 
>> I declare my class binding like this:
>> 
>>     class_<Actor, Actor_wrapper, boost::shared_ptr<Actor> >("Actor")
>>     .def(constructor<const string &>())
>>     .def("draw", &Actor::draw, &Actor_wrapper::default_draw)
>>     ];
>> 
>> And the function I'm trying to call from C++ is like this:
> Sorry, I hit accidentaly sent my message before it was finished, here is the 
> function:
> 
> void bindLuaPart()
> {
>        luabind::wrapped_self_t& wrapper = 
>            luabind::detail::wrap_access::ref(*this);
>        if (wrapper.m_strong_ref.is_valid()) {
>            LOG_W("Double call to wrap_Component::bindLuaPart");
>            return;
>        }
>        wrapper.get(wrapper.state());
>        wrapper.m_strong_ref.set(wrapper.state());
> }
> 
> This is highly dependent on implementation details though, but it works at 
> least with the original luabind.
> 
> ------------------------------------------------------------------------------
> See everything from the browser to the database with AppDynamics
> Get end-to-end visibility with application monitoring from AppDynamics
> Isolate bottlenecks and diagnose root cause in seconds.
> Start your free trial of AppDynamics Pro today!
> http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk
> _______________________________________________
> luabind-user mailing list
> lua...@li...
> https://lists.sourceforge.net/lists/listinfo/luabind-user