"-group" )
            shift
            mk_workdir
            get_listargs "$@"
            unset group groupkey grp x
            for ((i=1; i<${#ARGS_ARRAY[@]}; i++)); do
                grp[x++]="$(abspath "${ARGS_ARRAY[i]}")"
            done
            GROUP_IN_FILES=( "${GROUP_IN_FILES[@]}" "${grp[@]}" )
            group="$(for ((b=0; b<${#grp[@]}; b++)); do echo -e "${grp[b]}"; done)"
            groupkey=$(( ${ARGS_ARRAY[0]} - 1))
            GROUP[groupkey]="$group"
            # create symlinks to ease substitution later
            for c in ${!grp[@]}; do
                ln -sv "${grp[c]}" $WORK_DIR/group-$((groupkey+1))-$((c+1))
            done
            GROUPING=:
            ;;