From: justinj@... (Justin Johnson)
Date: 2002-07-02T18:51:15+09:00
Subject: Re: Ruby implementation Q's

> I have heard this mentioned a lot and never understood these comments. Can
> you explain in more detail? Why do you think finalization happens too late
> to be useful?

Imagine that there is a class that manages bitmaps, sounds or other
forms of large binary data.  Perhaps a mixture, even.  An instance of
the class is created and used.  When the instance is no longer
referenced, it hangs around until a garbage collection is initiated,
whereby it is deleted and then possibly finalized.  The problem is,
the data is hanging around until that point.  Python (if I can mention
the 'P' word here!) gets around this by using a reference counting
system for garbage collection.  The moment an objects reference hits
0, it can be safetly destructed.  The problem is, I don't think
reference counting is a good garbage collection strategy for a number
of reasons.  The problem is, you cannot predict when the finalization
is going to happen.

When an object is 'destroyed' it would broadcast to all it's objects
for destruction thus creating a chain reaction.

Ruby is a wonderfully dynamic language.  On the fly, you can create
variables for classes/modules/instances.  Wouldn't it be consistent to
be able to delete them too?

Justin Johnson
justinj@mobiusent.com