$>declare MYSTERY_CMD=$(which mystery) && echo "All set." || echo "Adding to missing array ... " All set.
$>MYSTERY2_CMD=$(which mystery2) && echo "All set." || echo "Adding to missing array ... " Adding to missing array ... Declaring a variable doesn't seem risky enough to eat up the return code. Is there a reason for this? I doubt that it would break anything to change. It's a lot more intuitive and syntactically streamlined to check for missing packages/software at the initial declaration as a sanity check.
