Re: [boost] Re: cyclic ptr (was: Re: Re: Re: Re: Re: Re: Re: Proposals: p2m offsets, prebuild<>, squad_ptr<> (of course))

From: Greg Colvin (Gregory.Colvin_at_[hidden])
Date: 2002-09-07 10:09:59

At 08:45 AM 9/7/2002, Larry Evans wrote:
>Greg Colvin wrote:
>
>>It's been my intent to create a version of cyclic_ptr that
>>would be compatible with intrusive_ptr and shared_ptr, but
>>I haven't had time or motivation.  The weak_ptr companion to
>I've been working on the something similar.  I also realized that
>the method of garbage collection and method of internal pointer
>enumeration were independent.  The two garbage collection methods
>I'm working on are your's and the local mark scan of Lin's.  

Tell me more about how you are using Lin's method.

>I've got
>an enumeration:
> enum
>gc_methods
> { gc_local_mark_scan
>   //^ Lins's method
> , gc_global_mark_scan
>   //^ Christopher's(or Colvin's) method
> };
>
>to select which one in a specialized class.  I've got another enumeration
>to specify the method of enumerating the internal pointers:
>
> enum
>ip_methods
> { ip_offset_iterator
>   //^ this method has the proxies record their offsets in
>   //  their containing subject.  Also, containers(e.g. vector)
>   //  of proxies record their offsets from their containing subject
>   //  as well as a function to iterate over the contained
>   //  proxies (e.g. something based on vector::iterator ).
>   //
>   //  This method off accessing internal pointers is based
>   //  on:
>   //      David L. Detlefs
>   //        "Garbage collection and runtime typing as a C++ library"
>   //        _USENIX C++ Conference_, Portland, Oregon
>   //        August 1992
>   //        USENIX Association
>   //
>   //  However, in addition to Detlef's method, this method also
>   //  is able to access pointers within containers, such as
>   //  vector<prox_type> or list<prox_type> by using template,
>   //  scoped_cyclic_container.
> , ip_assign_op_switch
>   //^ this method uses subject::operatr= with self as arg to cause
>   //  all proxies (i.e. internal pointer) within the subject
>   //  to call their operator= via the virtual children method.    //  This proxy::operator= then calls the static parent method.
>   //  This is Greg Colvin's method.
> };
>I've got a driver working with gc_local_mark_scan and ip_offset_iterator.
>I'm still working on the others.
>
>You're review and comments would be useful.  Should we work on it
>in the sandbox or should I just upload the still incomplete code to
>files?

Whatever works for you is fine with me.  For now just email me your code.