----- Original Message -----
> From: Peter Otten <__pete...@web.de>
> To: python-list@python.org
> Cc:
> Sent: Sunday, August 3, 2014 11:37 AM
> Subject: Re: Correct type for a simple "bag of attributes" namespace object
>
> Albert-Jan Roskam wrote:
>
>> I find the following obscure (to me at least) use of type() useful exactly
>> for this "bag of attributes" use case:
>>>>> employee = type("Employee", (object,), {})
>>>>> employee.name = "John Doe"
>>>>> employee.position = "Python programmer"
>>>>> employee.name, employee.position, employee
>> ('John Doe', 'Python programmer', <class
> '__main__.Employee'>)
>
> Are you sure you know what you are doing? The above is equivalent to
>
>>>> class employee:
> ... name = "John Doe"
> ... position = "Python programmer"
> ...
>>>> employee.name, employee.position, employee
> ('John Doe', 'Python programmer', <class
> '__main__.employee'>)
>>>> type(employee)
> <class 'type'>
>
> Basically you are using classes as instances. While there is no fundamental
> difference between classes and instances in Python you'll surprise readers
> of your code and waste some space:
Yes, I know that it is equivalent, but I have always found it kind of ugly to
use class() just to bundle a number of items. Like you are 'announcing OOP'
(not sure how to put this into words), and then it's merely a simple bundle. Or
maybe it's just me being silly, because it's even in the Python tutorial:
https://docs.python.org/2/tutorial/classes.html#odds-and-ends
>>>> import sys
>>>> sys.getsizeof(employee)
> 976
>>>> class Employee: pass
> ...
>>>> employee = Employee()
>>>> employee.name = "John Doe"
>>>> employee.position = "Python programmer"
>>>> sys.getsizeof(employee)
> 64
Wow, I was not aware of that at all. So they are not equivalent after all.
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