From: Justin Collins <justincollins@...>
Date: 2009-10-15T12:10:18+09:00
Subject: Re: dynamically access class constants?

Marli Ba wrote:
> I've been looking for a method similar to:
>
> Obj.send(:method)
>
> but to access class constants.  So if I have:
>
> class MyObj
>   MY_CONSTANT_1
> end
>
> I want to access MyObj::MY_CONSTANT_1 by using a variable like foo =
> MY_CONSTANT_1 and then MyObj::send(:foo), but obviously send is only
> meant to work with methods and not constants.
>
> Is there any way to do this?  I've looked but am having difficulty
> finding anything.
>
> Thanks,
> Marli
>   

I am slightly confused by your example, but you definitely need 
Module#const_get: http://www.ruby-doc.org/core/classes/Module.html#M001689

irb(main):001:0> class A
irb(main):002:1> B = 1
irb(main):003:1> end
=> 1
irb(main):004:0> A.const_get(:B)
=> 1

-Justin