From: Joel VanderWerf <vjoel@...>
Date: 2008-04-06T02:57:21+09:00
Subject: Re: The ||= assignment operator

David A. Black wrote:

> The only time this matters is with hashes that have default values. In
> every other case, as far as I know, x = x || y also describes what's
> happening. But the expansion which describes *every* case is x || x =
> y.

One other case (a very similar one) in which it matters is this:

   class C
     def x; @x || 5; end
     def x=(v); puts "assigning @x=#{v}"; @x = v; end
   end

   c = C.new
   c.x ||= 3 # no effect
   p c.x     # 5
   c.x = 2   # assigning @x=2
   p c.x     # 2

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407