- From: Dave Raggett <dsr@w3.org>
- Date: Wed, 21 Mar 2007 16:30:45 +0000 (GMT)
- To: public-html@w3.org, www-forms@w3.org
On the HTML list, we have talked about the desire to make it easy for all kinds of people to edit web content from children to grandparents. It shouldn't be necessary to know and understand the details of HTML markup and CSS, let alone the DOM and how to write event handlers in JavaScript. Smart editing tools can automate the generation of markup, style sheets and scripts, so that authors don't need to know about that level of detail. The problem comes when you want to reload the document and make further changes. If the semantics have been compiled into JavaScript, it is essentially impractical to get them back. This is the problem of how to round trip semantics from the editor to the document and back again. If HTML is a final form medium like PDF that is essentially write only, then the solution is to author in a different format and have the machine automatically generate HTML for delivery to web browsers. At this point you might be saying that you have no difficulties with writing scripts and revel in the delights of PHP, ASP and Ruby on Rails, so what is all this nonsense about declarative formats? Well the answser is while that may be fine for you, it restricts the pool of people who can author web content for anything more complex than emails and blog entries to a relatively small clique. It is surely time to democratise web authoring! Spreadsheets are attributed as having turned the personal computer from a hobby into a business tool, see [1]. Visicalc was introduced by Dan Bricklin in 1979 and soon followed by Lotus 1-2-3 and later yet by Microsoft Excel. Visicalc was one of the first "killer apps" that drove people to buy computers to be able to run it. The Web has yet to offer anything like the simplicity with which anyone can create a spreadsheet with some text and a few formualae, without any knowledge of programming. It is time to fix that! Web Forms 2.0 provides incremental extensions to HTML4 forms, such as the ability to specify simple data types for numbers, dates and times, as well as the means to state min and max values, or to constrain entered text to match regular expressions. This is good! What it currently lacks is the means to state simple formulae for calculated fields, and the means to state simple constraints such as this field must be greater than the value of that field, or that this field must be filled out under such and such conditions, or that this group of fields is relevant and should be shown when a given field has a particular value. These can all be stated using simple JavaScript expressions. You can see a range of such examples at [2]. The equivalent WF2 examples are at [3] [1] http://en.wikipedia.org/wiki/Spreadsheet [2] http://www.w3.org/2007/03/XForms-Transitional/#examples [3] http://www.w3.org/2007/03/WF2/ Web Forms 2.0 isn't cast in concrete, and it is time to look at how HTML Forms can take advantage of simple spreadsheet like expressions. Yes there are some details in Web Forms 2.0 that might need to change, but democratising web authoring is well worth it. I have shown that it can be made to work on pretty much all modern web browsers, so the technical problems are definitely do able. If you have a technical question, I will do my best to answer it. For people who hear the word declarative and reach for their AK-47, think of expressions as a way of writing event handlers that that even your mom will get. p.s. if HTML is condemned to be a final form medium, it isn't the end of the world as there are standards based XML formats that work just fine and lots of experience at hand in automatically adapting the content to particular devices. But do we want to give up on HTML that easily! Dave Raggett <dsr@w3.org> http://www.w3.org/People/Raggett
Received on Wednesday, 21 March 2007 16:30:48 UTC