# File lib/zip/zipfilesystem.rb, line 463
      def foreach(aDirectoryName)
        unless @file.stat(aDirectoryName).directory?
          raise Errno::ENOTDIR, aDirectoryName
        end
        path = @file.expand_path(aDirectoryName).ensure_end("/")

        subDirEntriesRegex = Regexp.new("^#{path}([^/]+)$")
        @mappedZip.each { 
          |fileName|
          match = subDirEntriesRegex.match(fileName)
          yield(match[1]) unless match == nil
        }
      end