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Re: Understanding how is a function evaluated using recursion

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On Thursday, September 26, 2013 4:54:22 AM UTC+5:30, Arturo B wrote:
> So I know what recursion is, but I don't know how is 
> 
>                        flatten(i)
> 
> evaluated, what value does it returns?

When you are a noob, who do you ask? The gurus.
When you are a guru who do you ask? The computer!

And its really quite easy to ask the computer directly. Here's your code with a extra prints

def flatten(l):
    print ("Received: %s" % l)
    ret = []
    for i in l:
        if isinstance(i, list) or isinstance(i, tuple):
            ret.extend(flatten(i)) #How is flatten(i) evaluated?
        else:
            ret.append(i)
    print ("Returning: %s" % ret)
    return ret 

Now run it with a couple of different inputs (not neglecting the trivial cases) and see if it does not self-explain.

If still confusing, come back and ask!

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Thread

Understanding how is a function evaluated using recursion Arturo B <a7xrturodev@gmail.com> - 2013-09-25 16:24 -0700
  Re: Understanding how is a function evaluated using recursion Josh English <Joshua.R.English@gmail.com> - 2013-09-25 16:59 -0700
  Re: Understanding how is a function evaluated using recursion MRAB <python@mrabarnett.plus.com> - 2013-09-26 01:07 +0100
  Re: Understanding how is a function evaluated using recursion Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-26 00:10 +0000
  Re: Understanding how is a function evaluated using recursion Dave Angel <davea@davea.name> - 2013-09-26 00:26 +0000
  Re: Understanding how is a function evaluated using recursion Terry Reedy <tjreedy@udel.edu> - 2013-09-25 21:12 -0400
  Re: Understanding how is a function evaluated using recursion rusi <rustompmody@gmail.com> - 2013-09-25 21:04 -0700
  Re: Understanding how is a function evaluated using recursion Neil Cerutti <neilc@norwich.edu> - 2013-09-26 14:18 +0000
    Re: Understanding how is a function evaluated using recursion Neil Cerutti <neilc@norwich.edu> - 2013-09-26 14:23 +0000
      Re: Understanding how is a function evaluated using recursion Peter Cacioppi <peter.cacioppi@gmail.com> - 2013-09-28 13:24 -0700
  Re: Understanding how is a function evaluated using recursion rusi <rustompmody@gmail.com> - 2013-09-29 20:41 -0700

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