- From: Sampo Syreeni <decoy@iki.fi>
- Date: Thu, 17 Oct 2002 23:21:39 +0300 (EEST)
- To: Bertilo Wennergren <bertilow@gmx.net>
- cc: "'www-html@w3.org'" <www-html@w3.org>
On 2002-10-17, Bertilo Wennergren uttered to 'www-html@w3.org': >If the details of the numbering are essential, and the document would >suffer if those details are not presented exactly as whished, then they >are part of the content, and should be specified directly in the >content. If the details of the numbering are essential, then what we're talking about isn't an HTML ordered list, but a DL or a TABLE, both of which have the capability of actually associating fixed labels with the list entries. At the same time we all know that using DL's and TABLE's isn't really good, either. There is a simple reason for this. Namely, the idea of a numbered list has been presentational from the very beginning. Numbered list items on paper serve a double role. First, they distinguish an ordered (numbered) list from an unordered (bulleted) one. Second, the numbers work as a way to refer to the items, individually. Where we talk about an unordered list it's usually sufficient to refer to "one of the items, above". Where an ordered list is involved, we need to distinguish the items based on their position in the order. Hence, we utilize the numbering: "item 2 in the above list". At the same time the numbers indicate that the "block progression direction" of the content coincides with the order relation of the data being represented by the list. In hypertext there's no need for such constructs. If references need to be made, they can be made with links. If order needs to be discerned, that can be accomplished through any of a *huge* number of ways. What remains of the semantics of numbered lists is plain order. Not the reference to numbers (i.e. item labelling), but the plain order. That's what HTML encodes, because more is not needed in the context of hypertext. Getting a list to look like the way it has to be printed on paper is presentation, and so is strictly secondary to the structural semantics of HTML. Of course, that's not the whole story. Once there's lots of any particular representation going around, the representation itself is bound to be extended. It will be used to stand in for things it originally didn't, and adapted to needs it originally didn't serve. Thus the way ordered lists are represented on paper lead people to conceive of lists as arbitrary labels associated with specific content, instead of visual indications of order merged with link endpoints. The "3a" example is about representing revision history, while inversed numbering is mostly about poetic value. The latter is used when presenting a list in straight order for some reason doesn't sound as good. (E.g. countdowns to something, acknowledgeing winners, and the like, or just artistic effect.) If either of them is coding-worthy, they should acquire their own, explicit representation in HTML. That's simply because HTML does away with that sort of thing. Its lists represent order, as a physicist would conceive it -- there either is an order, or there isn't. Definition lists seem rather out of place, here, until you realize that they're meant to stand in for all of the other stuff, all the ways the list syntax has been used to map generalized labels to bits and pieces of content. In this framework, a totally ordered relation will be represented by an OL, a bag by a UL, and a discrete function by a DL. If you want things like "3a", inverse numbering, or whatever, you'll use DL until there's a dedicated semantic structure in HTML which encodes what you mean. You don't use the representational aspects of normal lists to mimic what you want to mean, however far they could theoretically be extended. >If it's in CSS then it's just eye-candy. Eye-candy is OK, but then you >should be able to live with a totally different presentation and a >totally different numbering scheme. You should, indeed. That's pretty much the point, in its entirety. -- Sampo Syreeni, aka decoy - mailto:decoy@iki.fi, tel:+358-50-5756111 student/math+cs/helsinki university, http://www.iki.fi/~decoy/front openpgp: 050985C2/025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2
Received on Thursday, 17 October 2002 16:21:41 UTC