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From: Marko Rauhamaa <marko@pacujo.net>
Newsgroups: comp.lang.python
Subject: Re: Ah Python, you have spoiled me for all other languages
Date: Fri, 22 May 2015 23:34:47 +0300
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Ian Kelly <ian.g.kelly@gmail.com>:

> An "object" in Javascript is basically just a collection of
> properties. For example:
>
> js> typeof([1, 2, 3])
> "object"
> js> typeof({a: 1, b: 2, c: 3})
> "object"
>
> Here's what happens when you try to access a property on null:
>
> js> null.foo
> typein:18:0 TypeError: null has no properties

That's not all that different from Python, where object() returns a
fresh instance at each invocation. However:

   >>> object().x = 3
   Traceback (most recent call last):
     File "<stdin>", line 1, in <module>
   AttributeError: 'object' object has no attribute 'x'

Why are object instances immutable in Python?


Marko