Is there a way to specify a superclass at runtime?

Chris Colbert sccolbert at gmail.com
Mon Oct 5 11:33:01 EDT 2009


that's a good idea.

Thanks!


On Mon, Oct 5, 2009 at 4:18 PM, MRAB <python at mrabarnett.plus.com> wrote:
> Chris Colbert wrote:
>>
>> because when i import this module, the classes will already be
>> determined by the intitial flag setting.
>>
>> i.e.
>> SIMULATION = False
>>
>> class SimController(object):
>>   def foo(self):
>>       print 'bar'
>>
>> class RealController(object):
>>   def foo(self):
>>       print 'baz'
>>
>> if SIMULATION:
>>   SuperKlass = SimController
>> else:
>>   SuperKlass = RealController
>>
>> class Controller(SuperKlass):
>>   pass
>>
>>
>>
>>
>>
>> In [2]: import testcontroller
>>
>> In [3]: testcontroller.SIMULATION
>> Out[3]: False
>>
>> In [4]: c = testcontroller.Controller()
>>
>> In [5]: c.foo()
>> baz
>>
>> In [6]: testcontroller.SIMULATION = True
>>
>> In [7]: c = testcontroller.Controller()
>>
>> In [8]: c.foo()
>> baz
>>
> [snip]
> You could put the Controller class inside a factory function:
>
> def Controller():
>        if SIMULATION:
>                SuperKlass = SimController
>        else:
>                SuperKlass = RealController
>        class Controller(SuperKlass):
>                pass
>        return Controller()
> --
> http://mail.python.org/mailman/listinfo/python-list
>



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