From: David Alan Black <dblack@...>
Date: 2000-12-17T23:03:09+09:00
Subject: [ruby-talk:7505] Re: flatten_by(n)

On Sun, 17 Dec 2000, Ben Tilly wrote:

> I am away from my home box again, but something like this
> should work:
> 
>   class Array
>     def flatten_once
>       res = []
>       each do |e|
>         if e.is_a? Array
>           res += e
>         else
>           res.push e
>         end
>       end
>       res
>     end
>   end


And, what's more....

  def flatten_once
    res = []
    for e in self     # a little faster than each
      res.push(*e)
    end
    res
  end


10000 iterations:

             user     system      total        real
mine:    1.210000   0.040000   1.250000 (  1.268839)
yours:   3.040000   0.000000   3.040000 (  3.042355)

This is the part I love -- where the code almost evaporates,
and actually gets faster and stronger.  (Whose .sig was it
that says something about gaining functionality by deleting
code?)

Also, just for fun (haven't tweaked this one yet):

  def flatten_once!
    res = flatten_once
    clear.concat res
  end


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav