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From: Michael McGlothlin <michaelm@plumbersstock.com>
Date: Fri, 28 Oct 2011 12:10:14 -0600
Subject: Fast recursive generators?
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:15110

I'm trying to generate a list of values where each value is dependent
on the previous value in the list and this bit of code needs to be
repeatedly so I'd like it to be fast. It doesn't seem that
comprehensions will work as each pass needs to take the result of the
previous pass as it's argument. map() doesn't seem likely. filter() or
reduce() seem workable but not very clean. Is there a good way to do
this? About the best I can get is this:

l = [ func ( start ) ]
f = lambda a: func ( l[-1] ) or a
filter ( f, range ( big_number, -1, -1 ) )


I guess I'm looking for something more like:

l = do ( lambda a: func ( a ), big_number, start )


Thanks,
Michael McGlothlin