It’s useful – and crucial – in RubyMotion to define attribute accessors so only a weak reference is held to avoid cyclic redundancies.

You can define a simple DSL:

class Class
  def weak_attr_accessor(*my_accessors)
    my_accessors.each do |accessor|
      define_method(accessor) do
        instance_variable_get("@#{accessor}")
      end
 
      define_method("#{accessor}=") do |accessor_value|
        instance_variable_set("@#{accessor}", WeakRef.new(accessor_value))
      end
    end
  end
end

Then use it like this:

class SomeView < UIView
  weak_attr_accessor :view_controller
end

I’m pretty sure I copied (and maybe modified the code a little) from this gist, but it looks like the link doesn’t work anymore.

UPDATE: Exactly 1 year later (no kidding), I finally wrote a weak_attr_accessor because I wanted to use it in purplish-layout.