Note that of the examples given, only Perl 6 and Common Lisp do two things
that help immensely simplify the result:
1. reference the built-in * operator directly, without having to wrap it in
a lambda expression;
2. actually name the function "!"
The Lisp version suffers from the lack of a built-in range constructor.
On Wed, May 27, 2009 at 2:21 PM, Mark J. Reed <markjr...@gmail.com> wrote:
>
> In Haskell it may be called fold (well, foldl and foldr), but the concept
> has has a variety of names. Two of the more common ones are "reduce" and
> "inject"; I believe Perl6 chose "reduce" for consistency with the Perl5
> List::Util module. Common Lisp and Python also call it "reduce":
>
> (defun ! (n)
> (reduce #'* (loop for i from 1 to n collecting i)))
>
>
> def fact(n):
> return reduce(lambda x,y: x*y, range(1,n+1))
>
>
> While Ruby calls it "inject".
>
>
> def fact(n)
> (1..n).inject { |x,y| x*y }
> end
>
>
> Perl 6 has a lot of functional features. IMO the nice thing about its
> version of reduce is the way it's incorporated into the syntax as a
> metaoperator.
>
> --
> Mark J. Reed <markjr...@gmail.com>
>
>
>
--
Mark J. Reed <markjr...@gmail.com>
