The goal is to create a regex that matches exactly the eight target strings (email, URL, date, product ID, international phone, IPv6, currency, and html snippet) and nothing more. I use an alternation pattern (using the | operator) to match each of these exactly. Special characters that might otherwise be interpreted as regex metacharacters (such as ., +, ?, and $) are escaped appropriately. The final regex will match exactly one of these items as they appear in the text, and nothing else.