Re: Remove Luabind ownership on C++ pointer?

On Fri, Oct 1, 2010 at 12:15 AM, neosettlers <[email protected]> wrote:
> Thx everyone for the inputs,
>
>> Well, this is a very rare request. Having to explicitly state that instances
>> should be destroyed would screw over almost everyone.
>
> I think it is at least practical to have the choice to managed your memory
> yourself without reinventing the wheel.

Sure, and you do have that choice.

>> Basically, you have some class whose instances somehow manages their own
>> lifetime?
>
> Of course, all classes are registered and unregister by an object manager.

Right. Typically this would be done by either:

  1. Creating the object in lua, and then have some function on the manager
      that explicitly takes ownership, or...

  2. Having a factory function on your manager that creates the object and
      returns non owning pointer.

(2) works automatically, and luabind has adopt() for (1). Perhaps we
should have a release_ownership() policy similar to adopt(), that can
be used post-construction, I'm not sure. That said, I believe your
problem can be handled as I show below.

> I managed to solved my problem in modifying the source directly:
>
> object_rep::~object_rep()
> {
>        if (!m_instance)
>            return;
>  ///    m_instance->~instance_holder();
>        deallocate(m_instance);
> }

Did you try what I posted? In fact, it can be done in an even simpler way:

  class_<Whatever, Whatever*>("Whatever")

Makes luabind hold the newly created instance in a raw Whatever*, and
thus won't delete it.

-- 
Daniel Wallin
BoostPro Computing
http://www.boostpro.com

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