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Date: Sat, 17 Aug 2013 12:31:01 -0500
From: Tim Chase <python.list@tim.thechases.com>
To: python-list@python.org
Subject: Re: Python getters and setters
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Xref: csiph.com comp.lang.python:52638

On 2013-08-17 17:18, Steven D'Aprano wrote:
> # Yes, this is good, consistent design
> len(myrecord.field)
> len(obj.data)
> len(data.value)
> len(collection[key])

I would also add that, if the primary goal of your class is to
encapsulate the data, you can do

  class MyClass:
    def __init__(self, ...):
      self.data = []
    def __len__(self):
      return len(self.data)

which allows for the even clearer

  my_obj = MyClass(...)
  manipulate(my_obj)
  if len(my_obj) > 42:
    do_important_stuff()

-tkc