Ternary operator (?:) in Bash

Is there a way to do something like this

int a = (b == 5) ? c : d;

using Bash?

ternary operator ? : is just short form of if/else

case "$b" in
 5) a=$c ;;
 *) a=$d ;;
esac

Or

 [[ $b = 5 ]] && a="$c" || a="$d"