-- The Timber compiler <timber-lang.org>
--
-- Copyright 2008-2009 Johan Nordlander <nordland@csee.ltu.se>
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module Stack where

struct Stack a where 
  push :: a -> Action
  pop  :: Action
  top  :: Request a
  size :: Request Int

stk = class
   xs := []
   
   push x = action
     xs := x : xs

   pop = action
     xs := tail xs
 
   top = request
     result (head xs)

   size = request
     result (length xs)

   result Stack{..}