-v VAR (conditional operator)

true if the shell variable VAR is set.

Bash 4 and later also allow to check the value of an array element, e.g. [[ -v myArray[1] ]].

Links

• Bash manual
• POSIX specification of test

Examples

Different ways to test if a shell variable is set:

1 2 3 4 5

test -v HOME && echo "set" [ -v HOME ] && echo "set" # Bash [[ -v HOME ]] && echo "set" [[ -v myArray[1] ]] && echo "set"