On May 4, 1:34 am, Cameron Simpson <c...@zip.com.au> wrote: > On 03May2010 22:02, rickhg12hs <rickhg1...@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.
Ah, an explicit "return" is required. Thanks! [To bad there's no tail recursion optimization.] 8-( -- http://mail.python.org/mailman/listinfo/python-list
