[Python-3000] Using *a for packing in lists and other places

[Georg Brandl]

Guido van Rossum schrieb:
> Thomas Wouters suggests some new syntax:
> 
> http://bugs.python.org/issue2292
> 
>>>> a, b, *c = range(5)
> 
>>>> *a, b, c = a, b, *c
>>>> a, b, c
> ([0, 1, 2], 3, 4)
>>>> [ *a, b, c ]
> [0, 1, 2, 3, 4]
>>>> L = [ a, (3, 4), {5}, {6: None}, (i for i in range(7, 10)) ]
>>>> [ *item for item in L ]
> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
> 
> Also, yielding everything from an iterator:
> 
>>>> def flatten(iterables):
> ....     for it in iterables:
> ....         yield *it
> ....
>>>> L = [ a, (3, 4), {5}, {6: None}, (i for i in range(7, 10)) ]
>>>> flatten(L)
> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
> 
> What do people think?

As Brett says, it's a good generalization. +1 from me.

Georg


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