From: "ara.t.howard" <ara.t.howard@...>
Date: 2008-07-08T01:00:38+09:00
Subject: Re: Another logical precedence question


On Jul 7, 2008, at 9:28 AM, -j b- wrote:

> Why the two types of behavior based (as far as I can tell) on the type
> of the second parameter to 'or'?

it's always the *same* behavior, namely

   (something = this) or that

so when 'that' happens to be a method call which prints out usage and  
exits you get the behavior you want be accident, when you do

   user_map = ARGV.shift or DEFAULT_MAP

you simply do this

cfp:~ > irb
 >> user_map = nil or Hash.new
=> {}
 >> user_map
=> nil

in otherwords

   (user_map = nil) or DEFAULT_MAP

so the 'or' bit is essentially a noop you execute after assigning nil  
to the user_map

regards.

a @ http://codeforpeople.com/
--
we can deny everything, except that we have the possibility of being  
better. simply reflect on that.
h.h. the 14th dalai lama