Use POSIX character classes, like a pro

dotfiles/bash/main.bashrc

@@ -203,7 +203,7 @@ yum_hasbin() {
             *)      dnf provides "*/bin/$bname" ;;
         esac \
           | grep '^.' \
-          | grep -E '^[0-9a-zA-Z_:.-]+ :'
+          | grep -E '^[[:alnum:]_:.-]+ :'
     done
 }