bash 变量跟随#*=,##*=的含义

ARGS="$@"
echo ${ARGS}
for arg in ${ARGS}
do
    case ${arg} in
        --packageName=*)
        echo packageName: ${arg#*=}
        packageNameArg=${arg#*=}
        ;;
        --branch=*)
          echo 分支: ${arg#*=}
          branchArg="${arg#*=}"
        ;;
        --commit=*)
        echo commit: ${arg#*=}
        commitArg=${arg#*=}
        ;;
        --commitTimes=*)
        echo commitTimes: ${arg#*=}
        commitTimesArg=${arg#*=}
        ;;
        *)
        echo "未知参数 $arg"
        # unknown option
        # usage
        ;;
    esac
done