From: aero6dof@... (Alan Chen)
Date: 2003-08-23T01:58:13+09:00
Subject: Re: Class variables - a surprising result

Ged Byrne <gedb01@yahoo.co.uk> wrote in message news:<20030822093558.59647.qmail@web10801.mail.yahoo.com>...
> If this idiom could be replaced with some clear syntax
> I think it would be a good thing.
> 
> > 
> > > If you want to access these in instance methods,
>  you need to do:
> > >
> > > class Foo
> > >    def instance_meth
> > >       p self.class.class_eval { @var }
> > >    end
> > > end 

The beauty of ruby is that you can clean this up if you 
really want. 

class Module
  # generate "static" variables more like C++ or Java
  def attr_reader_static(*syms)
    syms.each { |sym|
      module_eval( %Q[def self.#{sym}; @#{sym}; end] )
    }
  end

  def attr_writer_static(*syms)
    syms.each { |sym|
      module_eval( %Q[def self.#{sym}=(val); @#{sym} = val; end] )
    }
  end

  def attr_accessor_static(*syms)
    attr_reader_static(syms)
    attr_writer_static(syms)
  end
end


class Foo
  attr_accessor_static :staticvar
end

Foo.staticvar = 11
p Foo.staticvar  => 11