[Python-ideas] Function to unnest for-statements

[George Sakkis]

On Sun, May 25, 2008 at 4:01 AM, Arnaud Delobelle
<arnodel at googlemail.com> wrote:
>
> On 23 May 2008, at 08:15, Carl Johnson wrote:
>
>> So, what do you think? Is this a common enough need that it should be
>> built into itertools? The main namespace? Or should we leave it out, since
>> adding it would encourage people writing O(n^x) algorithms? If nothing else,
>> list members can enjoy rewriting this function for fun.
>
> It is already in itertools:
>
> Python 3.0a4+ (py3k:62388, Apr 19 2008, 15:34:00)
> [GCC 4.0.1 (Apple Inc. build 5465)] on darwin
> Type "help", "copyright", "credits" or "license" for more information.
>>>> from itertools import product
>>>> for v in product(*[[True, False]]*3):
> ...     print(v)
> ...
> (True, True, True)
> (True, True, False)
> (True, False, True)
> (True, False, False)
> (False, True, True)
> (False, True, False)
> (False, False, True)
> (False, False, False)

Or a bit more readable:

>>> for v in product([True, False], repeat=3):
...         print(v)

George