auto classes and finalizers

[Jarrett Billingsley]

"Dave" <Dave_member at pathlink.com> wrote in message 
news:e11vjk$1fou$1 at digitaldaemon.com...
> Long and short of it is I like Mike's ideas regarding allowing dtors for 
> only
> auto classes. In that way, the GC wouldn't have to deal with finalizers at 
> all,
> or at least during non-deterministic collections. It would also still 
> allow D to
> claim RAII because 'auto' classes are something new for D compared to most 
> other
> languages.

Hmm.  'auto' works well and good for classes whose references are local 
variables, but .. what about objects whose lifetimes aren't determined by 
the return of a function?

I.e. the Node class is used only in LinkedList.  When a LinkedList is 
killed, all its Nodes must die as well.  Since the Node references are kept 
in the LinkedList and not as local variables, there's no way to specify 
'auto' for them.

Then you start getting into a catch-22.  Okay, so you need to delete all 
those child Nodes in the dtor of LinkedList, meaning that LinkedList has to 
be made auto so it can have a dtor.  But what if a linked list reference has 
to exist at global level, or in a struct?  There is no function return to 
determine when to delete the list.  So you have to make LinkedList non-auto, 
but then that means that you can't delete all those child nodes since you 
don't have a dtor / finalizer, etc..

I think RAII is nice, but it doesn't seem to fix everything.  Unless, of 
course, it were extended to deal with these odd cases.