# File lib/money/currency.rb, line 194
      def unregister(curr)
        if curr.is_a?(Hash)
          key = curr.fetch(:iso_code).downcase.to_sym
        else
          key = curr.downcase.to_sym
        end
        existed = @table.delete(key)
        @stringified_keys = nil if existed
        existed ? true : false
      end