From: "bpettichord@..." <bpettichord@...>
Date: 2006-05-21T17:05:08+09:00
Subject: Re: foo= methods don't get called inside instance scope without explicit receiver

I'm not sure of your specific situation, but i've found this to help in
these circumstances:

class Module
  def dsl_accessor(*symbols)
    symbols.each { |sym|
      class_eval %{
        def #{sym}(*val)
          if val.empty?
            @#{sym}
          else
            @#{sym} = val.size == 1 ? val[0] : val
          end
        end
      }
    }
  end
end

Bar.dsl_accessor :foo
b = Bar.new.
b.instance_eval { foo 1 }          #=> 1
b.instance_eval { foo }             #=> 1

See http://www.artima.com/rubycs/articles/ruby_as_dsl3.html for more.