Moonbase

class Module
  private
  def override_method( name, &body )
    begin
      supr = instance_method( name )
    rescue NameError
      supr = lambda {}
    end
    define_method( name ) { |*args|
      body.call( supr.bind(self), *args )
    }
  end
end

class Bar
  def bar
    p self
    p 1
  end
end

class Foo < Bar
  override_method( :bar ) { |supr|
    supr.call
    p self
    p 2
  }
  override_method( :bar ) { |supr|
    supr.call
    p self
    p 3
  }
end

Foo.new.bar

Now if I could just figure out how to re-jigger self when calling the block passed to override_method, as define_method obviously does…