Question

Presumably i have a instance var @foo

It is set inside def initialize so i can track when it is initialized.

However i also need to track when it is destroyed.

Are there some “hook” for this? Just like method_defined or included?

Something like instance_variable_destroyed foo?

Answer 1

You basically hook the garbage collector.
You need to use a define_finalizer.

define_finalizer(@foo, proc {|id| puts "Destroyed #{id}"})