adjust generated Scala to make it work with scalac -old-syntax and -new-syntax, although the latter is not regularly tested;
#!/usr/bin/env bash
set -e
$ISABELLE_LUALATEX root
$ISABELLE_BIBTEX root
$ISABELLE_LUALATEX root
$ISABELLE_LUALATEX root
./isa-index root
$ISABELLE_LUALATEX root