# File lib/action_controller/caching/fragments.rb, line 87
      def expire_fragment(key, options = nil)
        return unless cache_configured?
        key = fragment_cache_key(key) unless key.is_a?(Regexp)
        message = nil

        instrument_fragment_cache :expire_fragment, key do
          if key.is_a?(Regexp)
            cache_store.delete_matched(key, options)
          else
            cache_store.delete(key, options)
          end
        end
      end