From: dblack@...
Date: 2006-01-26T13:34:54+09:00
Subject: Re: class variable weirdness

Hi--

On Thu, 26 Jan 2006, Alex Combas wrote:

> hi David
>
> On 1/25/06, dblack@wobblini.net <dblack@wobblini.net> wrote:
>>> Can anyone explain why this is happening?
>> [...]
>>> puts "%s, %s" % (C.up,C.foo=10)
>>
>> You need an array there: [C.up, C.foo=10].  The way you've got it,
>> what's happening is that it's being parsed as two assignments:
>>
>>    C.up = 10
>>    C.foo = nil
>>
>
> Thanks I appreciate the quick reply, I think the () was a bit of
> python showing its roots.
> What I would like to do now is get instances of those classes and use the
> methods that I've defined but I cant figure out how, without changing the class.
>
> class A
>  @@foo=1
>  def self.foo=(n)
>    @@foo = n
>  end
> end
> puts "%s" % A.foo=10
> a = A.new
> #this does not work for an instance
> #puts "%s" % a.foo=10

Instances of A don't have a foo method, so you would indeed have to
change the class to give them one.  Is there a reason you don't want
to in this particular case?


David

-- 
David A. Black
dblack@wobblini.net

"Ruby for Rails", from Manning Publications, coming May 1, 2006!
http://www.manning.com/books/black