Could someone explain the following?
>>> a = {1}
>>> b = {2}
>>> a & b == set()
True
>>> a & b == {}
False
Why is this choice made?
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Dimitris Leventeas
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1@skyl Set literals were added ~2.7 I believe. Edit: Yup, it's [a 3.1 feature backported into 2.7](http://docs.python.org/dev/whatsnew/2.7.html#python-3-1-features) as it's a non-breaking change. – Gareth Latty May 05 '12 at 19:15
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Your code a & b == {} is comparing a ANDed with b with {}, an empty dictionary. So, the result of the and and an empty dictionary are different and the result is false.
octopusgrabbus
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mata
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`a or b` gives `set([1])` whereas `a | b` gives `set([1,2])`. What do the operators mean then? – Abhranil Das May 05 '12 at 19:07
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1@AbhranilDas see [this](http://docs.python.org/library/stdtypes.html#set) - `|` is the same as `union`, `or` does the same as always, returning the first element which evaluates to `True` – mata May 05 '12 at 19:10
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3@inspectorG4dget If you want a dict comprehension, put a `key: value` pair there instead. E.g: `{i: i+1 for i in range(5)}` will produce a dict. – Gareth Latty May 05 '12 at 19:13