(Newbie) Class constants from included modules

ruby-talk
1

I'd like to make a class constant using a module -- I cannot use <
because I am extending unit_test. -- Here's the idea:

module One
   @@constant="constant"
end

module Two
   def work
      puts(@@constant)
   end
end
class Constant_work
   include One
   include Two
end
Constant_work.new.work

IRB gives me:
NameError: uninitialized class variable @@constant in Two

How can I get what I want to happen?

Dale

···

--
Posted via http://www.ruby-forum.com/.

2

Hi --

I'd like to make a class constant using a module -- I cannot use <
because I am extending unit_test. -- Here's the idea:

module One
  @@constant="constant"
end

That's not a constant; it's a class variable (completely different
thing).

module Two
  def work
     puts(@@constant)
  end
end
class Constant_work
  include One
  include Two
end
Constant_work.new.work

IRB gives me:
NameError: uninitialized class variable @@constant in Two

How can I get what I want to happen?

   module One
     C = "constant"
   end

   module Two
     include One
     def work
       puts C
     end
   end

   class ConstantWork
     include Two
   end

   ConstantWork.new.work # constant

Constant identifiers begin with an uppercase letter. The @@ thing is
a class variable, which is a very different (and much less useful)
construct.

David

···

On Sat, 9 Jun 2007, Dale wrote:

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