Can my own objects support tuple unpacking?
Scott David Daniels
Scott.Daniels at Acm.Org
Thu Mar 27 00:04:23 EDT 2008
Patrick Toomey wrote:
> ... I am trying to figure out how tuple unpacking behavior works....
> a,b,c,d = e
>
> Is a method called, such as __getitem__ for each index on the left
> (0,1,2,3)? I thought this was logical, ...
>
> class Foo:
> def __getitem__(self, index):
> print index
> return 1
_So_ close.
class Foo(object): # _Never_ use old-style without a reason
def __getitem__(self, index):
print index
if index < 3:
return index * 5 # just to see
raise IndexError('Zapped') # The secret -- run out.
-Scott David Daniels
Scott.Daniels at Acm.Org
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