Re: [boost] discussion of garbage collection in C++

Subject: Re: [boost] discussion of garbage collection in C++
From: Bastek (snibisz_at_[hidden])
Date: 2009-04-21 14:08:44

On 21 Kwi, 18:44, "Simonson, Lucanus J" <lucanus.j.simon..._at_[hidden]>
wrote:
> I prefer to have a graph object that owns all graph nodes and
> deallocates them all in its destructor than have "liberated" graph
> nodes that can be assigned between different graphs.  
> Stl style is already providing the big productivity boost that GC claims.  
> Since the graph and geometry data structures are small and many in
> number it is better (in terms of both space and time) to store them in
> vectors and copy them around than allocate them dynamically through
> any mechanism including garbage collection.  I don't think GC offers
> any advantage over my current style of graph or geometry programming
> in terms of either productivity or performance of the code generated.  
> Cyclical ownership is just bad design.  All the objects in the cycle have
> the same "life" and an object that encapsulates that relationship and
> can be used to scope them as a unit is the obvious solution, not GC.  
> If the argument for GC is because it makes bad design less bad, then
> it can't win over the argument for good design.  
>
> I never have problems with leaks in my graph or geometry algorithms
> because I never type new and delete execpt in the rarest of circumstances,
> and even then the ownership is clear and they are deallocated in the
> destructor of an object, making the code exception safe.  GC solves
> a problem that does not exist for me.  If other people still have this
> problem they should learn how to apply C++ in a way that doesn't lead
> to such problems, not rely on GC to let them implement sloppy design.  
> C++ can be as productive to program in as Java if you use it well,
> and memory pooling with RAII will always outperform GC.

struct User;
struct Group
{
    std::vector<User*> users;
};

struct User
{
    Group* group;
};

Taking into account that the data can be used in multiple modules.
Do you know when and where to release the memory for this type of
objects?

C++ language, enforces restrictions on mapping the structures of
databases, because that does not have a Garbage Collector.