Random examples

deathbob_1.rb

class Bob
  def self.blocky
    yield
  end
end

module Death
  def call_blocky
    Bob.blocky do
      puts self
    end
  end
end

class Another
  include Death 
end

# Another.new.call_blocky #=> #<Another:0x000001009c10e8>

deathbob_2.rb

class Runnee
  def self.called
    puts self
  end
end

class Middle
  def self.caller(&block)
    runner = Runnee.new
    runner.instance_exec &block
  end
end

class Runner < Middle
  def self.doit
    caller do
      called
    end
  end
end

# Runner.doit #=> #<Runnee:0x000001009c73a8>