From: gabriele renzi <surrender_it@...>
Date: 2005-07-31T20:31:03+09:00
Subject: Re: Higher Order Functions

Nickolay Kolev ha scritto:
> Hi guys,
> 
> I have recently started learning Ruby having some background in  Python 
> and Prolog. Being a fan of functional programming I want to  port the 
> goopy functions (http://goog-goopy.sourceforge.net/ 
> goopy.functional.html) in Ruby despite most of them having  
> straightforward equivalents in Ruby already. Just as an exercise. I  
> also saw it as a good way to teach myself about modules. And  eventually 
> about unit testing. :-)

great plan :) even if I'm a bit disappointed that the library seem to be 
(almost) a list handling  library.

> My plan is to put all the functions in a module called Functional and  
> call them like Functional.func_name(params).
> 
> in fruby.rb:
> 
> module Functional
> 
>   def Functional.every(f, lst)
>     lst.collect { |element| f(element) }
>   end
> 
> end

Notice you could just do
module Functional
   def every... end
   def any other... end
   extend self
end

so that you could call it via Functiona.f and yet retain the ability to 
include the module (say, in Enumerable ;)

I also second the suggetsion to generally use a block wehenever possible 
(i.e. 99% of the time)