clarified argument formats: explicit Unit, allow XML.Elem as well;
tuned messages: prefer single quotes for JSON output;
#!/usr/bin/env bash
set -e
FORMAT="$1"
VARIANT="$2"
isabelle logo HOL
isabelle latex -o "$FORMAT"
isabelle latex -o bbl
./isa-index root
isabelle latex -o "$FORMAT"
[ -f root.out ] && "$ISABELLE_HOME/src/Doc/fixbookmarks" root.out
isabelle latex -o "$FORMAT"