4 ms·

That is not XHTML.

• nurettin 7y ago
  <input value="how about this? />"/>
  • unlinkr 7y ago
    That is a valid XHTML tag (if I remember correctly) and can be matched perfectly fine by a regex.
    • nurettin 7y ago
      Perhaps something like "([^"]*)" could skip what is inside the string literal. Unless there is "<input" in the string literal, then where you start parsing becomes very important.
      • unlinkr 7y ago
        That pattern would indeed match a quoted string. I don't see how it would matter if the quoted string contains something like "<input". It can contain anything except a quote character.
        • nurettin 7y ago
          It just makes the starting offset of the regex input important.
          • unlinkr 7y ago
            Sure. But that would be true for any parsing technique. No parser known to man would be able to produce a valid parse if you start it in the middle of a quoted string!
• hk__2 7y ago
  What about <a>this <!-- </a> --> </a> <!-- </a> -->?
  • unlinkr 7y ago
    Yes you can tokenize this with a regular expression and extract the valid start and end tags. If comments in XHTML could nest you would have a problem. But this is not the case.
    • hk__2 7y ago
      > Yes you can tokenize this with a regular expression and extract the valid start and end tags. So you need more than a regular expression, hence your premise is incorrect.
      • unlinkr 7y ago
        No, you don't need more than a regular expression. If you want to extract elements, i.e. match start tags to the corresponding end tags, then you need a stack-based parser. But just to extract the start tags (which is the question) a regular expression is sufficient. The original question is a question about tokenization, not parsing, which is why a regular expression is sufficient.