instance method map

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/locale/fallbacks.rb, line 75
      def map(mappings)
        mappings.each do |from, to|
          from, to = from.to_sym, Array(to)
          to.each do |to|
            @map[from] ||= []
            @map[from] << to.to_sym
          end
        end
      end