Tuple assignment and generators?
invalidemail at aerojockey.com
Fri May 5 19:16:27 CEST 2006
> I guess the take-away lesson is to steer clear from any reliance on
> object identity checks, if at all possible.
> Are there any other such
> "optimizations" one should like to know about?
You don't have to know about them, as long as you use the operators
== tests equality. is tests identity. Use is ONLY when you are
testing whether two things are the same object. Otherwise, use ==.
When deciding which operator to use, ask yourself this: would the
result still be true if they were different objects with the same
value? If yes, then use ==. 0 == 0 should be true even if the two
zeros are different objects.
You should test for singleton objects with is. None, NotImplemented,
and Ellipsis are singleton objects; this is part of the language and
not an implementation detail. You can rely on it.
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