On Wednesday 02 December 2015 18:51:03 Aymeric Augustin wrote:
>
> We could implement a property that returns an object:
>
> - that is still callable, for backwards compatibility
> - that evaluates correctly in a boolean context
>
> Then we can consider deprecating the ability to call it.
>
>
> class CallableBool:
>
> def __init__(self, value):
> self.value = value
>
> def __bool__(self):
> return self.value
>
> def __call__(self):
> return self.value
>
> def __repr__(self):
> return 'CallableBool(%r)' % self.value
>
> CallableFalse = CallableBool(False)
>
> CallableTrue = CallableBool(True)
>
More general alternative:
class IdempotentCallMixin(object):
def __call__(self): return self
However, you can't extend bool, so
class CallableBool(IdempotentCallMixin, bool): pass
does not work, and you'd have to do something like
class CallableBool(IdempotentCallMixin, int): pass
which is less nice (because of __repr__ etc)
Shai
