Operator Precedence/Boolean Logic
antoon.pardon at rece.vub.ac.be
Thu Jun 23 06:54:55 EDT 2016
Op 23-06-16 om 11:53 schreef Marko Rauhamaa:
> Antoon Pardon <antoon.pardon at rece.vub.ac.be>:
>> Op 23-06-16 om 11:10 schreef Marko Rauhamaa:
>>> The __len__ method is not guaranteed to execute in O(1). See:
>>> <URL: https://docs.python.org/3/reference/datamodel.html?highlig
>> As far as I can see, neither is the __bool__ method.
> Correct, but in the absence of an __empty__ method, __bool__ gives the
> class the best opportunity to check for emptiness quickly.
> This is not only a theoretical concern. It's quite common for data
> structures not to maintain an element count because it's extra baggage
> that's not always needed and any application could keep a track of.
> However, an emptiness check is often trivial.
Maybe something like this:
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