def increment(key, amount = 1, options = {})
      last = nil
      @stack.each {|s| last = s.increment(key, amount, options) }
      last
    end
def increment(key, amount = 1, options = {})
      last = nil
      @stack.each {|s| last = s.increment(key, amount, options) }
      last
    end
(see Proxy#increment)