prefac is just a normal factorial function with recursion factored out. fix prefac 5 gives 120, for example. 

On Tue, May 4, 2010 at 12:13 AM, Ivan Miljenovic <ivan.miljenovic@gmail.com> wrote:
On 4 May 2010 13:30, Luke Palmer <lrpalmer@gmail.com> wrote:
> Here is a contrived example of what I am referring to:
>
> prefac f 0 = 1
> prefac f n = n * f (n-1)
>
> fac = (\x -> x x) (\x -> prefac (x x))

I can't work out how this works (or should work rather); is it meant
to be using church numerals or something (assuming that they have been
made an instance of Num so that - and * work)?

--
Ivan Lazar Miljenovic
Ivan.Miljenovic@gmail.com
IvanMiljenovic.wordpress.com
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