I don't know how to title this question but anyway
a="$(file . * | grep -i pgp)" || echo "no such files found! " && exit \
&& b=$(echo "$a" | fzf --cycle --height=15) && [ -n "$b" ] \
&& gpg --import "$b"
I'm confused about this. When variable a does not exist prints echo "no such files found! " and exits but when does exist doesn't print the message and exits as well. How can I do to exit only when no value is passed to variable a, in other words, when variable a does not exist.