From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2005-10-20T04:12:08+09:00
Subject: Re: Functional with Ruby

On Thu, 20 Oct 2005, Andreas Semt wrote:

> Hello list,
>
> here a really simple Haskell function, which sums all elements of a list
> (from the book "The Haskell School of Expression"):
> --------------------------------
> listSum [] = 0
> listSum (x : xs) = x + listSum xs
> --------------------------------
>
> Which is the best way to say it in Ruby (functional style)? Don't use
> 'enum.inject', please!


harp:~ > cat a.rb
list_sum = lambda{|*list| list.flatten!; list.empty? ? 0 : list.shift + list_sum[list] }

p list_sum[ 0b101000,  0b10 ]

harp:~ > ruby a.rb
42

-a
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