Neal Becker <ndbeck...@gmail.com> wrote:
> What I'm trying to do is make a callable whose behavior is switched
> based on some criteria that will be fixed for all calls. In my
> example, this will ultimately be determined by the setting of a
> command line switch.
>
If you want different behaviour its usually best to use different classes.
You can keep all the common behaviour in a base class and just override the
__call__ method for the different behaviour. Then use a factory function to
decide which class to instantiate or else override __new__ and make the
decision there. e.g.
>>> class X(object):
def __call__(self):
return 0
def __new__(cls, i):
if i!=0:
cls = Y
return object.__new__(cls)
>>> class Y(X):
def __call__(self):
return 1
>>> x = X(0)
>>> x()
0
>>> y = X(1)
>>> y()
1
>>> isinstance(x, X)
True
>>> isinstance(y, X)
True
P.S. I don't know what you did in your post but your Followup-To header is
pointing to a group on gmane which makes extra work for me replying. Please
don't do that.
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