Recursive functions not returning lists as expected

[Cameron Simpson]

On 03May2010 22:02, rickhg12hs <rickhg12hs at gmail.com> wrote:
| Would a kind soul explain something basic to a python noob?
| 
| Why doesn't this function always return a list?
| 
| def recur_trace(x,y):
|   print x,y
|   if not x:
|     return y
|   recur_trace(x[1:], y + [x[0]])

You need:
    return recur_trace(x[1:], y + [x[0]])

Otherwise the function returns None.
-- 
Cameron Simpson <cs at zip.com.au> DoD#743
http://www.cskk.ezoshosting.com/cs/

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