- From: A Rafael D Teixeira <rafaelteixeirabr@hotmail.com>
- Date: Mon, 23 Jul 2001 14:46:34 -0300
- To: www-forms@w3.org
>... >OPTION 1: ><xsd:sequence> > <xsd:element ref="xform:submitInfo" minOccurs="0"/> > <xsd:element ref="xform:model" minOccurs="0"/> > <xsd:element ref="xform:instance" minOccurs="0"/> > <xsd:element ref="xform:bind" minOccurs="0" maxOccurs="unbounded"/> ></xsd:sequence> >This means authors MUST write the elements in exactly the specified >sequence. >Changing the order of the sequence in any way results in an invalid >form. Thatīs is unacceptable. Even if we count on automatic tools (Page Editors, XForms Back-End Preprocessors, ...) to help us, it makes "open", meaning "extensible", forms much harder to develop. Just to say how important it is: I have hundreds of extensible forms in my web application today, 'extended' diferently for each of my thousand customers, whose have today just one choice of browser (IE5.x) to use because I couldnīt make my javascript/XML solution work on anything else. XForms, if kept easily extensible and then broadly deployed, would marvelously improve the situation. >Unfortunately XML Schema, with which we are mainly concerned, doesn't >support this. Schema only supports <sequence>, as above, or <choice>. I think itīs time for version 1.1 of Schemas. They probably dropped the initial support for unordered sequences of elements, to easy the job on "verifiers", so that they can be smaller and faster (obviously a requirement on mobile platforms). Itīs harder to verify out-of-sequence itens with multiplicity restrictions, because you have to keep separate counters, but I think itīs better to have a <xsd:unorderedSequence> than having to code all the permutations and have the verifier check all of then, what is possibly worst-performing. >Another option in Schema, <all>, works only with single elements. If we >restrict ourselves to maxOccurs=1 on every element, then we >could use the <xsd:all> connector... If changing Schemas direction/evolution is out of question, or not a fast enough route, using <xsd:all> looks not terribly bad for the <xform> definition, but for form controls:... They need "freedom" to mix easily with xhtml, xmath, ..., and even with non-standard things like "Flash". Just a question, xhtml is "schematable"? More properly, is there a XML Schema to validate properly a xhtml document/page? If it exists and copes with the highly nestable and unordered sequences of div, p, span ... we can follow it as a guideline. Rafael Teixeira Brazilian Developer _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
Received on Monday, 23 July 2001 13:47:06 UTC