1-counter.py

from enum import Enum

CounterEvent = Enum('CounterEvent', 'UP DOWN')
    
def counter():
  def apply(f, x):
    return f(x)

  def handle_event(e):
    etype, data = e
    if etype is CounterEvent.UP:
      return (lambda x: x + data)
    elif etype is CounterEvent.DOWN:
      return (lambda x: x - data)
  return accumulate(apply, 0, handle_event)

class accumulate:
  def __init__(self, f, init, handle_event):
    self.f = f
    self.init = init
    self.handle_event = self.handle_event
    
  def get_value(self):
    return self.init
  
  def handle_event(self, e):
    self.init = self.f(self.handle_event(e), self.init)

2-Counter.hs

module Counter where

counter :: Behaviour (Event CounterEvent) Integer
counter = accumulate ($) 0 (\e -> case e of
  Up n -> (+n)
  Down n -> (subtract n))

data CounterEvent = Up Integer | Down Integer