Anchor(faq66)

I want to check if [[ $var == foo || $var == bar || $var == more ]] without repeating $var n times.

Here's a portable solution: 

   case $var in
      foo|bar|more) ... ;;
   esac

And here's one that uses =~ (which requires bash 3.0 or higher). This only works in bash 3.1, not in bash 3.2 (and is untested in 3.0): 

   if [[ $var =~ '^(foo|bar|more)$' ]]; then
      ...
   fi

I'd just stick with the case, myself. --GreyCat