From: Ken Bloom <kbloom@...>
Date: 2008-03-03T01:09:56+09:00
Subject: Re: What should this print?

On Sun, 02 Mar 2008 05:04:47 +0000, Bouquet wrote:

> Hi,
> 
> I was expecting the code below to print 1, 1, but I get 1, nil.
> 
> old = nil
> [1,1].each do |n|
>    if n != old
>      x = 1
>      old = n
>    end
>    p x
> end

After the first iteration, old is now 1. In the second iteration, n=1, so 
1==1 and the code in if statement doesn't execute. Since x wasn't defined 
outside of the block, it's created a new (or not) in each iteration, and 
here it wasn't created, so its value when read (p x) is nil.

--Ken

-- 
Ken (Chanoch) Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/