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Re: Simple recursive sum function | what's the cause of the weird behaviour?

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On Sat, Jul 6, 2013 at 10:37 PM, Russel Walker <russ.pobox@gmail.com> wrote:
> This works:
> - - - - - -
>>>> x = [[1], [2], [3]]
>>>> supersum(x)
> 6
>>>> supersum(x, [])
> [1, 2, 3]
>>>>
>
>
> This does not:
> - - - - - - -
>>>> x = [[[1], [2]], [3]]
>>>> supersum(x, [])
> [1, 2, 1, 2, 3]
>>>>

You have a problem of specification here. What should supersum do with
the list [1]? Should it recurse into it, or append it as a list? It
can't do both. For a list flattener, you would need to either use
.append for each element you come across, or .extend with each list,
with some kind of check to find whether you should recurse or not.

Still, it's a fun thing to play with. I like code golfing these sorts
of trinketty functions, just for fun :)

ChrisA

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Simple recursive sum function | what's the cause of the weird behaviour? Russel Walker <russ.pobox@gmail.com> - 2013-07-06 05:37 -0700
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Russel Walker <russ.pobox@gmail.com> - 2013-07-06 05:54 -0700
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Russel Walker <russ.pobox@gmail.com> - 2013-07-06 05:59 -0700
    Re: Simple recursive sum function | what's the cause of the weird behaviour? Peter Otten <__peter__@web.de> - 2013-07-06 15:19 +0200
    Re: Simple recursive sum function | what's the cause of the weird behaviour? Joshua Landau <joshua.landau.ws@gmail.com> - 2013-07-06 19:43 +0100
      Re: Simple recursive sum function | what's the cause of the weird behaviour? Rotwang <sg552@hotmail.co.uk> - 2013-07-06 21:10 +0100
        Re: Simple recursive sum function | what's the cause of the weird behaviour? Rotwang <sg552@hotmail.co.uk> - 2013-07-06 21:25 +0100
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Chris Angelico <rosuav@gmail.com> - 2013-07-07 03:22 +1000
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Terry Reedy <tjreedy@udel.edu> - 2013-07-06 14:47 -0400
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Russel Walker <russ.pobox@gmail.com> - 2013-07-07 09:13 -0700
  Re: Simple recursive sum function | what's the cause of the weird behaviour? Russel Walker <russ.pobox@gmail.com> - 2013-07-07 09:44 -0700

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