# aside: don't use upper-case names for your own variables. ENV, specifically, is reserved
# per http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html
is_dev() { [[ $ENV = "$DEV" ]]; }
if is_dev; then
相反,如果要存储结果:
if [[ $ENV = "$DEV" ]]; then is_dev=1; else is_dev=0; fi
if (( is_dev )); then ...