Is there a list of all the if switches for use in bash scripting? Sometimes I see someone using it and I wonder what the switch they're using actually does.Example is the -z in this one. I know how to use it, but I don't know where it was derived from.if [ -z $BASH_VERSION ]; then    echo -e Error: this script requires the BASH shell!    exit 1fiAny references, guides, posts, answers would be appreciated. Thank you!
List of 'if' switches anywhere?
bash;shell script;terminal;bash script;command switch