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Comment by vbezhenar

4 days ago

So Python is not OOP language? You can't hide fields.

5 comments

vbezhenar

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nr378  4 days ago

You can hide fields in Python with a little bit of gymnastics:

  class EncapsulatedCounter:
      def __init__(self, initial_value):
          _count = initial_value

          def increment():
              nonlocal _count
              _count += 1
              return _count

          self.increment = increment


  counter = EncapsulatedCounter(100)
  new_value = counter.increment()
  print(f"New value is: {new_value}")

  • d0mine  4 days ago

    Usually, a simple function is enough:

        def make_counter(start=0):
      count = start
      def incr():
        nonlocal count
        count += 1
        return count
      return incr

    Example:

        >>> c = make_counter()
    >>> c()
    1
    >>> c()
    2

    But it hides nothing:

        >>> c.__closure__[0].cell_contents
    2
    >>> c.__closure__[0].cell_contents = -1
    >>> c()
    0

    "private" in Python is cultural, not enforced. (you can access `self.__private` from outside too if you want).