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comp.lang.ruby

Re: How to use a class_variable into a Module

Heesob Park

5/19/2008 1:49:00 PM

Hi,

Iñaki Baz Castillo wrote:
> Hi, I want to declare a class_variable in class A.
> Class A includes a Module M and I want some methods in M using the
> class_variable but I get some problem:
>
> -------------------
> module M
> def kk
> #puts (eval %{ #{send('class').class_variables[0]} })
> puts @@class_var
> end
> end
>
> class A
> include M
> @@class_var = "kaka1"
> end
>
> a = A.new
> a.kk
> NameError: uninitialized class variable @@class_var in M
> from ./class_attr1.rb:4:in `kk'
> -------------------
>
>
> I understand the problem. Because the nature of class variables when
> the Module M uses @@ it looks into a class variable defined in same
> class/module.
>
> Is there any way I could use a class A @class_var into a included M
> module methods? If not then I'll use a normal attribute but I don't
> like it since it's a constant value that could perfectly be a class
> variable instead of initialiting it in each A instance creation.
>
Here is a working code:

module M
@@class_var = nil
def kk
puts @@class_var
end
end

class A
include M
@@class_var = "kaka1"
end

a = A.new
a.kk


Regards,

Park Heesob
--
Posted via http://www.ruby-....
2 Answers

Iñaki Baz Castillo

5/19/2008 3:11:00 PM

0

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Iñaki Baz Castillo

5/19/2008 3:17:00 PM

0

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