If you want access to the member variables, you have to pass them into the finalize() method so they are available to the finalizer, just like the name variable.

ObjectSpace.define_finalizer( self, self.class.finalize(name) } )

and even after I remove that, the syntax doesn’t define a callable method. Instead it just calls the method

You can wrap it in a Proc

ObjectSpace.define_finalizer(self,proc{|id| self.class.finalize(name)})

but that creates a closure which binds self, preventing the object from being garbage collected!

How on earth are you meant to get access to the member variables from a finaliser?

The API invites this bug because there the object isn’t passed to the block, and thusly people think they want the object to be in the closure to they can do something with it when it’s being finalized. Ruby’s GC can’t deal with this, and thus the passing of #object_id to the block.

In Rubinius, I’m working on adding true finalizers: code that runs when an object was just detected as garbage, but can access the object itself. The finalizer code can even resurrect the object and it will be finalized later. Not yet sure what the API for this will be (a #finalize method on the object maybe?) but it should help in some ways.