The HTML5 Super Friends: The spec should clarify that an author can use XHTML or HTML syntax, that it is a coding style preference. It would be great if Henri could add a toggle to the validator that will check for syntax. Something along the lines of “Also check for XHTML syntax validity.”
At the moment Henri is a bit firefox-focused, but I’ll volunteer to help to the extent that I can, with one key proviso, namely that the “super friends” produce concrete test cases for what they want flagged. The test cases I have in mind should be very simple to write: a 10 to 30 line HTML document which demonstrates the condition to be flagged, and the text of an even-toned message to be produced.
The reason I’m insisting on test cases is that while this request sounds deceptively simple, the fact of the matter is that there are a lot of unanswered questions. At the present time I have neither the time nor the inclination to work out all of the details for the corner cases. I’ll even go further: I don’t even care if any particular test meets the criteria of “XHTML syntax validity”, I just care that the tests are properly vetted.
I’ll initially work with Mike Smith to deploy the code on the W3C qa-dev site which you can experiment with. Note the (numerous) messages for unquoted attributes. Once this is good enough for wider consumption, I’ll get Henri to deploy the code to Validator.nu. Eventually this code will make it to the primary W3C site. People will also be able to download the source and deploy it within their own firewalls.
It is my hope that we can quickly iterate. Even if I only implement one major feature a week, getting to the 80% use case should be a matter of a month or two at most. A single well placed check should detect most unclosed tag issues. If there is one (or even several) situations which go undetected, providing additional test case(s) would ensure that these are caught in subsequent iterations. And over time, this will only improve.