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Author Jason.Baker
Recipients Jason.Baker, eric.araujo, ncoghlan, rhettinger
Date 2011-01-26.03:52:55
SpamBayes Score 0.00025701677
Marked as misclassified No
Message-id <1296013978.17.0.320781243661.issue11011@psf.upfronthosting.co.za>
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I'm not sure I understand how Raymond's alternative for trampoline works.  Let's take the factorial algorithm from wikipedia's page on tail recursion[1].  I've implemented the tail recursive version of the algorithm in Python using trampoline:

    from functools import trampoline, partial

    def factorial(n):
        def fact(i, acc):
            if i:
                return partial(fact, (i-1), (acc * i))
            else:
                return acc
        return trampoline(fact, n, 1)

    >>> factorial(5)
    120


How would I implement this using Raymond's alternative?

[1] http://en.wikipedia.org/wiki/Tail_call#Example_programs
History
Date User Action Args
2011-01-26 03:52:58Jason.Bakersetrecipients: + Jason.Baker, rhettinger, ncoghlan, eric.araujo
2011-01-26 03:52:58Jason.Bakersetmessageid: <1296013978.17.0.320781243661.issue11011@psf.upfronthosting.co.za>
2011-01-26 03:52:55Jason.Bakerlinkissue11011 messages
2011-01-26 03:52:55Jason.Bakercreate