extends to the end of the enclosing BLOCK or eval string, or to the next
successful pattern match, whichever comes first. If you want to use
parentheses to delimit a subpattern (e.g. a set of alternatives) without
-saving it as a subpattern, follow the ( with a ?.
+saving it as a subpattern, follow the ( with a ?:.
You may have as many parentheses as you wish. If you have more
than 9 substrings, the variables $10, $11, ... refer to the