Idiomatic bash: set default value for variable
bash, idioms
Solution
default value : ${parameter:-word} \
assign default value : ${parameter:=word} |_ / if unset or null -
error if empty/unset : ${parameter:?mesg} | \ use no ":" for unset only
use word unless empty/unset : ${parameter:+word} /
Problem
How can I set a default value for a bash variable in a concise, idiomatic way? This just looks ugly: ``` if [[ ! -z "$1" ]]; then option="$1" else option="default" fi ```