[Python-3000] PEP 3132: Extended Iterable Unpacking (original) (raw)

Christian Heimes lists at cheimes.de
Wed May 2 02:32:35 CEST 2007

Neville Grech Neville Grech wrote:

This reminds me a lot of haskell/prolog's head/tail list splitting. Looks like a good feature.

Agreed!

a*=range(5) hmmn maybe in such a case, whenever there is the * operator, the resulting item is always a list/tuple, like the following: a=[[0,1,2,3,4]] ?

Did you mean *a = range(5)? The result is too surprising for me. I would suspect that *a = range(5) has the same output as a = range(5).

*b = (1, 2, 3) b (1, 2, 3)

a, *b = (1, 2, 3) a, b 1, (2, 3)

*b, c = (1, 2, 3) b, c (1, 2), 3

a, *b, c = (1, 2, 3) a, b, c 1, (2,), 3

But what would happen when the right side is too small?

a, *b, c = (1, 2) a, b, c 1, (), 2

or should it raise an unpack exception?

This should definitely raise an exception

a, *b, c, d = (1, 2)

Christian

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