method_call.lua

-- $Id: methcall.lua,v 1.2 2004-06-12 16:19:43 bfulgham Exp $
-- http://shootout.alioth.debian.org
-- contributed by Roberto Ierusalimschy

--------------------------------------------------------------
-- Toggle class
--------------------------------------------------------------

Toggle = {}

function Toggle:value ()
  return self.state
end

function Toggle:activate ()
  self.state = not self.state
  return self
end

function Toggle:new (start_state)
  local o = {state = start_state}
  self.__index =self
  setmetatable(o, self)
  return o
end


--------------------------------------------------------------
-- NthToggle class
--------------------------------------------------------------

NthToggle = Toggle:new()

function NthToggle:activate ()
  self.counter = self.counter + 1
  if self.counter >= self.count_max then
    Toggle.activate(self)
    self.counter = 0
  end
  return self
end

function NthToggle:new (start_state, max_counter)
  local o = Toggle.new(self, start_state)
  o.count_max = max_counter
  o.counter = 0
  return o
end


-----------------------------------------------------------
-- main
-----------------------------------------------------------

function main ()
  local start = os.clock()
  local N = 250000

  local val = 1
  local toggle = Toggle:new(val)
  for i=1,N do
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
    val = toggle:activate():value()
  end
  print(val and "true" or "false")

  val = 1
  local ntoggle = NthToggle:new(val, 3)
  for i=1,N do
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
    val = ntoggle:activate():value()
  end
  print(val and "true" or "false")
  io.write(string.format("elapsed: %.8f\n", os.clock() - start))
end

main()