- From: Philip & Le Khanh <Philip-and-LeKhanh@royal-tunbridge-wells.org>
- Date: Thu, 26 Apr 2007 10:41:00 +0200
- To: "W3C HTML Mailing List" <www-html@w3.org>
- Cc: "Lachlan Hunt" <lachlan.hunt@lachy.id.au>
Lachlan Hunt wrote: > The HTML5 spec is attempting to define how to handle all HTML now and in > the future. With the unfortunate exception of IE, browsers will not be > adding additional DOCTYPE sniffing to distinguish between HTML5 andother > revisions. That is, I think at the very centre of this debate/argument/w-h-y, although this is the first explicit mention that I have seen. Web Apps 1 (I avoid calling it HTML5, since there is by no means universal agreement that Web Apps 1 should become HTML5) appears to be defining (amongst other things) a processing model that will allow all HTML pages to be processed in the same way (including an attempt to define the behaviour if a document is ill-formed). What I believe is really needed is about as diametrically opposed to this as can be imagined : a processing model which varies with the DOCTYPE. I have little objection to it defining a processing model which treats HTML 3.2 and earlier as tag soup. HTML 4.0 was a mistake, HTML 4.01 corrected the error and -- if it had been properly used in the wild -- could have been parsed and processed more rigorously : as it is, there is such a corpus of ill-formed legacy documents that one has little choice but to once again allow the tag-soup model. But HTML5 should be different. This is surely the time at which to say "enough is enough" : either a document is well-formed (in which case its processing is well-defined) or it is not, in which case the browser can process it as it will. There is <shout>no need</> for all browsers to handle something that /alleges/ to be HTML5 consistently if the document is defective (poorly formed). Indeed, if browsers /do/ vary wildly in their treatment of ill-formed HTML5 documents, there will be far greater pressure on /hoi polloi/ to write good, well-formed, HTML5 if they wish their offerings to be seen consistently. Thus, IMHO, HTML5 can be processed quite differently to earlier, legacy, DTDs and it should be quite correct for a conforming browser to switch processing models (from "lax" to "strict") when an HTML5 DTD is detected. To summarise, I think the following statement, taken from Web Apps 1, is fundamentally flawed and requires radical thinking if sanity is to prevail : 8.1.1. The DOCTYPE A DOCTYPE is a mostly useless, but required, header. DOCTYPEs are required for legacy reasons. When omitted, browsers tend to use a different rendering mode that is incompatible with some specifications. Including the DOCTYPE in a document ensures that the browser makes a best-effort attempt at following the relevant specifications. I would re-cast this along the lines of the following : 8.1.1. The DOCTYPE A DOCTYPE is a much abused, but required, header. Until the introduction of HTML5, DOCTYPEs have -- in the main -- been mere eye-candy at the start of a putative HTML document. With the introduction of HTML5, the DOCTYPE plays a vital role in determining the processing model for HTML documents. If a well-formed HTML5 DOCTYPE is found (in the syntactically correct position), a conforming browser is REQUIRED to adopt the strict processing model described elsewhere in this specification. If such a DOCTYPE is NOT found (or is found but in a position where its semantics are undefined), then a conforming browser is entitled to adopt any processing model that it deems fit. Philip Taylor
Received on Thursday, 26 April 2007 10:02:19 UTC