def ruby_to_vool(ruby_source)
      ruby_tree = Ruby::RubyCompiler.compile( ruby_source )
      unless(@vool)
        @vool = ruby_tree.to_vool
        return @vool
      end
      # TODO: should check if this works with reopening classes
      # or whether we need to unify the vool for a class
      unless(@vool.is_a?(Vool::ScopeStatement))
        @vool = Vool::ScopeStatement.new([@vool])
      end
      @vool << ruby_tree.to_vool
    end
def ruby_to_vool(ruby_source)
      ruby_tree = Ruby::RubyCompiler.compile( ruby_source )
      unless(@vool)
        @vool = ruby_tree.to_vool
        return @vool
      end
      # TODO: should check if this works with reopening classes
      # or whether we need to unify the vool for a class
      unless(@vool.is_a?(Vool::ScopeStatement))
        @vool = Vool::ScopeStatement.new([@vool])
      end
      @vool << ruby_tree.to_vool
    end
ruby_to_vool compiles the ruby to ast, and then to vool