From: "David A. Black" <dblack@...>
Date: 2009-06-24T02:40:47+09:00
Subject: Re: Is it the ruby way to implement #downto

Hi --

On Wed, 24 Jun 2009, Li Chen wrote:

> Skye Shaw!@#$ wrote:
>> Well, I'd hope that creating 3 unnecessary objects wouldn't be deemed
>> the Ruby way :^)
>> Most code I've seen would use each() instead of for i in (). Each is
>> faster anyways.
>
> I do it this way using each().
>
> def my_downto2(final=2)
>      (final..self).to_a.reverse.each do |i| yield i end
> end
>
> But I am still uncomfortable that I  have to use #to_a followed by
> #reverse to do the trick. Besides using while loops what is the best way
> to add a new method of #downto?

def my_downto(n)
   (-self..-n).each {|i| yield -i }
   self
end

:-)


David

-- 
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