From: "Kroeger, Simon (ext)" <simon.kroeger.ext@...>
Date: 2006-08-16T18:27:18+09:00
Subject: Re: [QUIZ] Newbie doubts about the quiz

 

> From: Daniel Martin [mailto:martin@snowplow.org] 
> Sent: Wednesday, August 16, 2006 4:21 AM
> 
> "Marcelo Alvim" <malvim@gmail.com> writes:
> 
> > 4) You guys could teach me a super-cool Ruby-esque way to 
> do that that
> > I can't even think about right now.
> 
> Note that what I did to solve this was at each step to copy the cells
> in the neighborhood of the current cell to a 13 by 13 array so that
> the current cell is the middle.  This then frees me from thinking
> about wraparound or bounds checking while computing which move to make
> next.
> 
> Of course, this is only possible if you have a fast way to copy a
> rectangular chunk of one two-dimensional array to another.  Since I
> was using NArray, I had that.

You know I like NArray, but perhaps there is an even 
cooler way this time :)

-----------------------------------------------
my_array = [1, 2, 3]
another_one = [1, 2, 3]

p my_array[-1] #=> 3 grmpf...
p another_one[-1] #=> 3 yeah, what else?

class << my_array
  def [] index
    return nil if index < 0
    super
  end
end

p my_array[-1] #=> nil, hehe, nice!
p another_one[-1] #=> 3 woot, woot
-----------------------------------------------

I don't know if this is really the right way, but the 
OP was asking for a super-cool Ruby-esque way, right?

cheers

Simon