def matches?(actual)
      @missing = @expected.reject {|e| actual.include?(e)}
      @extra = actual.reject {|e| @expected.include?(e)}
      @extra.empty? && @missing.empty?
    end
def matches?(actual)
      @missing = @expected.reject {|e| actual.include?(e)}
      @extra = actual.reject {|e| @expected.include?(e)}
      @extra.empty? && @missing.empty?
    end
:nodoc:all