python list pattern matching?

[Chris Rebert]

On Thu, May 28, 2009 at 3:57 PM, Terry Reedy <tjreedy at udel.edu> wrote:
> guthrie wrote:
>>
>> I want to do a functional like pattern match to get teh first two
>> elements, and then the rest of an array return value.
>>
>> For example, assume that perms(x) returns a list of values, and I want
>> to do this:
>>    seq=perms(x)
>>
>>    a = seq[0]
>>    b = seq[1]
>>    rest = seq[2:]
>> Of course I can shorten to:
>>    [a,b] = seq[0:2]
>>    rest  = seq[2:]
>>
>> Can I find use some notation to do this?
>>    [a,b,more] = perms(x)
>> or conceptually:
>>    [a,b,more..] = perms(x)
>
>>>> a,b,*rest = list(range(10))
>>>> a,b,rest
> (0, 1, [2, 3, 4, 5, 6, 7, 8, 9])
>>>> a,*rest,b = 'abcdefgh'
>>>> a,rest,b
> ('a', ['b', 'c', 'd', 'e', 'f', 'g'], 'h')

Note that this snazzy new syntax requires Python 3.0+

Cheers,
Chris
-- 
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