What is the difference bettween
[[ -n $VAR ]]
and
[[ -n ${VAR:-} ]]
?
When should I use second test?
What is the difference bettween [[ -n $VAR ]] and [[ -n ${VAR:-} ]]
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What is the difference bettween
[[ -n $VAR ]]
and
[[ -n ${VAR:-} ]]
?
When should I use second test?
The syntax
${VAR:-value}substitutesvaluewhen$VARis empty or unset. There is no particular reason (that I can think of) to use this syntax with an emptyvalue.