problem with the execution of an array of functions using cps (continuation passing style)

[Pablo Botelho <pablo.bcb@...>]

local f1 = function(context, continue)
  context.foo = 'foo'
  print 'i am function one'
  continue()
end
 
 
local f2 = function(context, continue)
  context.bar = 'foo'
  print 'i am function two'
  continue()
end
 
local f3 = function(context, continue)
  context.breno = 'magro'
  print 'i am function three'
  continue()
end
 
 
local f4 = function(context, continue)
  context.cafil = 'ratos'
  print 'i am function four'
  print 'ia am the last function of the array'
end
 
local context                = {}
local current_function_index = 0
local function_array         = { f1, f2, f3, f4 }
 
local continue = function()
  -- fetchs the current function of the 'function_array' variable
  current_function_index = current_function_index + 1
 
  print('index:' .. current_function_index)
 
  local current_function = function_array[current_function_index]
 
  -- tests to see if theres a next function to execute
  if type(current_function) == 'nil' then
    return error('can not call "continue" on last function of the chain')
  end
 
  -- executes the next function passing the context and the continuation
  current_function(context, continue)
end
 
continue()


-----------
The idea is to trigger the execution of the first function of the 'function_array' variable 
and then asynchronously trigger the next function in 'function_array' by 
calling the 'continue' argument
I can see why the error is happening but I cant figure a way to get it to work.