From: David Simas <dsimas@...>
Date: 2007-04-17T03:58:28+09:00
Subject: Re: factorial in ruby

On Tue, Apr 17, 2007 at 02:56:16AM +0900, Jason Roelofs wrote:
> No and most likely not.
> 
> def fact(n)
>  if n == 0
>    1
>  else
>    n * fact(n-1)
>  end
> end

For large enough n, this will overflow the stack.  Since Ruby doesn't
optimize tail-recursive functions (and the above isn't tail recursive,
anyway), you'd better write this function as a loop (left as an exercise).

DGS

> 
> Jason
> 
> On 4/16/07, Trans <transfire@gmail.com> wrote:
> >
> >Is factorial defined anywhere in Ruby's core or standard library. If
> >not will it be in 1.9+?
> >
> >Thanks,
> >T.
> >
> >
> >