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singleton ... again


On 2/12/14 12:50 PM, Asaf Las wrote:
> On Wednesday, February 12, 2014 7:48:51 AM UTC+2, Dave Angel wrote:
>>
>> Perhaps if you would state your actual goal,  we could judge
>>   whether this code is an effective way to accomplish
>>   it.
>> DaveA
>
> Thanks!
>
> There is no specific goal, i am in process of building pattern knowledge
> in python by doing some examples.
>

Not all patterns are useful.  Just because it's been enshrined in the 
GoF patterns book doesn't mean that it's good for Python.

I don't understand why you would like a class to pretend to make new 
instances, but actually lie and return the same instance over and over. 
  It makes them impossible to test: your unit tests all act on the same 
object, there's no way to start over with a fresh object.

If you only want one object, create just one, and use it everywhere.

-- 
Ned Batchelder, http://nedbatchelder.com