for isofile in $isopath/GNUSTEP-amd64-*.iso; do
  if [ -e "$isofile" ]; then
    regexp --set=isoname "$isopath/(.*)" "$isofile"
    submenu "$isoname ->" "$isofile" {
      iso_path="$2"
      loopback loop "$iso_path"
      menuentry "GNUSTEP" {
        bootoptions="findiso=$iso_path boot=live"
        linux (loop)/live/vmlinuz1 $bootoptions
        initrd (loop)/live/initrd1
      }
    }
  fi
done
