lib/Tools/build

   echo "Usage: isabelle $PRG [OPTIONS] [SESSIONS ...]"
   echo
   echo "  Options are:"
   echo "    -D DIR       include session directory and select its sessions"
   echo "    -R           operate on requirements of selected sessions"
+  echo "    -X NAME      exclude sessions from group NAME and all descendants"
   echo "    -a           select all sessions"
   echo "    -b           build heap images"
   echo "    -c           clean build"
   echo "    -d DIR       include session directory"
   echo "    -g NAME      select session group NAME"

   echo "    -l           list session source files"
   echo "    -n           no build -- test dependencies only"
   echo "    -o OPTION    override Isabelle system OPTION (via NAME=VAL or NAME)"
   echo "    -s           system build mode: produce output in ISABELLE_HOME"
   echo "    -v           verbose"
-  echo "    -x SESSION   exclude SESSION and all its descendants"
+  echo "    -x NAME      exclude session NAME and all descendants"
   echo
   echo "  Build and manage Isabelle sessions, depending on implicit"
   show_settings "  "
   echo
   exit 1

 
 ## process command line
 
 declare -a SELECT_DIRS=()
 REQUIREMENTS=false
+declare -a EXCLUDE_SESSION_GROUPS=()
 ALL_SESSIONS=false
 BUILD_HEAP=false
 CLEAN_BUILD=false
 declare -a INCLUDE_DIRS=()
 declare -a SESSION_GROUPS=()

 eval "declare -a BUILD_OPTIONS=($ISABELLE_BUILD_OPTIONS)"
 SYSTEM_MODE=false
 VERBOSE=false
 declare -a EXCLUDE_SESSIONS=()
 
-while getopts "D:Rabcd:g:j:k:lno:svx:" OPT
+while getopts "D:RX:abcd:g:j:k:lno:svx:" OPT
 do
   case "$OPT" in
     D)
       SELECT_DIRS["${#SELECT_DIRS[@]}"]="$OPTARG"
       ;;
     R)
       REQUIREMENTS="true"
+      ;;
+    X)
+      EXCLUDE_SESSION_GROUPS["${#EXCLUDE_SESSION_GROUPS[@]}"]="$OPTARG"
       ;;
     a)
       ALL_SESSIONS="true"
       ;;
     b)

 "$ISABELLE_TOOL" java "${JAVA_ARGS[@]}" isabelle.Build \
   "$REQUIREMENTS" "$ALL_SESSIONS" "$BUILD_HEAP" "$CLEAN_BUILD" "$MAX_JOBS" \
   "$LIST_FILES" "$NO_BUILD" "$SYSTEM_MODE" "$VERBOSE" \
   "${INCLUDE_DIRS[@]}" $'\n' "${SELECT_DIRS[@]}" $'\n' \
   "${SESSION_GROUPS[@]}" $'\n' "${CHECK_KEYWORDS[@]}" $'\n' \
-  "${BUILD_OPTIONS[@]}" $'\n' "${EXCLUDE_SESSIONS[@]}" $'\n' "$@"
+  "${BUILD_OPTIONS[@]}" $'\n' "${EXCLUDE_SESSION_GROUPS[@]}" $'\n' \
+  "${EXCLUDE_SESSIONS[@]}" $'\n' "$@"
 RC="$?"
 
 if [ "$NO_BUILD" = false -a "$VERBOSE" = true ]; then
   echo -n "Finished at "; date
 fi