From: mark sparshatt <msparshatt@...>
Date: 2004-08-13T06:00:19+09:00
Subject: Re: getting object attributes

Joe Laughlin wrote:

>David A. Black wrote:
>  
>
>>Hi --
>>
>>On Thu, 12 Aug 2004, Joe Laughlin wrote:
>>
>>    
>>
>>>I want to do something similar to this:
>>>
>>>class Foo
>>>  @goo = 2
>>>  @boo = 5
>>>end
>>>
>>>foo = Foo.new
>>>
>>>["goo", "boo"].each do |attribute|
>>>  puts foo.attribute   # should print out 2 on the first
>>>loop, 5 on the second loop
>>>end
>>>
>>>
>>>Ideas?
>>>      
>>>
>>Clarification requested:
>>
>>Do you want instances of foo to be able to get access to
>>the instance variables of Foo itself?  Or do you want
>>instances of Foo (such as foo) to have their own
>>instances variables called @goo and @boo, and reader
>>methods to access them?  You could do a bunch of
>>different variations on this but I'm not sure which
>>scenario you're trying to implement.
>>
>>
>>David
>>    
>>
>
>The second one, I believe.
>
>
>
>  
>
then this will do what you want

class Foo
  attr_reader :goo, :boo
  def initialize()
    @goo = 2
    @boo = 5
  end
end

foo = Foo.new

["goo", "boo"].each do |attribute|
  puts foo.send(attribute)   # should print out 2 on the first
loop, 5 on the second loop
end


@goo and @boo need to be initialised within a method or else they're 
instance variables of Foos metaclass rather than Foo itself.

--
Mark Sparshatt