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Date: Mon, 18 Apr 2011 12:10:32 +1000
Subject: Re: Feature suggestion -- return if true
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:3450

On Mon, Apr 18, 2011 at 12:04 PM, Dave Angel <davea@ieee.org> wrote:
> On 01/-10/-28163 02:59 PM, Chris Angelico wrote:
>>
>> =A0<snip>
>>
>> Sure. In my (somewhat contrived) example of factorials, that's going
>> to be true (apart from 0! =3D 0); and if the function returns a string
>> or other object rather than an integer, same thing. If there's the
>
> Just to be pedantic, by any reasonable definition, 0! =3D=3D one, not zer=
o.
>
> One reference: =A0http://en.wikipedia.org/wiki/Factorial
> 3rd sentence.

Hm! I never thought to check the definition... I just coded it up
quickly, and didn't even consider the possibility of a zero return
until the cache's loophole was challenged. Guess with a more correct
definition of factorial, it's even safer in the cache.

Question: How many factorial functions are implemented because a
program needs to know what n! is, and how many are implemented to
demonstrate recursion (or to demonstrate the difference between
iteration and recursion)? :)

ChrisA