- From: Frank Olken <olken@lbl.gov>
- Date: Thu, 28 Sep 2000 17:40:17 -0700
- To: ddj@mclink.it
- CC: "'www-xml-schema-comments@w3.org'" <www-xml-schema-comments@w3.org>, carnold@houston.rr.com, mtbryan@sgml.u-net.com
Frank Olken wrote: > > Dear Dario de Judicibus: > > The XML Schema Working Group has spent the last several months > working through the comments received from the public on the last-call > draft of the XML Schema specification. We thank you for the comments > you made on our specification during our last-call comment period, and > want to make sure you know that all comments received during the > last-call comment period have been recorded in our last-call issues > list (http://www.w3.org/2000/05/12-xmlschema-lcissues). > > Among other issues, you raised the point registered as issue > LC-61. simple-records: Allow record-style simple types? > > Please see the discussion below, and respond as to whether > this resolution is satisfactory. > > LC-61. simple-records: Allow record-style simple types? > ------------------------------------------------------- > > Issue Class: D Locus: datatypes Cluster: 03 constructors Status: > resolved > Assigned to: Frank Olken Originator: Dario de Judicibus > > Description > ------------ > > Should the datatypes spec be modified to allow the construction of types > with simple internal structure (e.g. to allow both quantity and units > of measure to be captured in the same simple type)? > > Interactions and Input > ---------------------- > > Cf. Suggestion: Microparsing support in XML Schema > Input from Dario de Judicibus: > "Dario de Judicibus" <ddj@mclink.it> to XML Schema Comments list, > Tue, 25 Apr 2000 23:12:02 +0200 > > Final comment: there is no way to combine types. For example, if I have > > <xsd:simpleType name="units"> > <enumeration value="cm" /> > <enumeration value="in" /> > </xsd:simpleType> > > I have no way to define > <height>12.4cm</height> > > by combining xsd:decimal and units. That might be very useful. > We might use a variant of pattern for that: > > <xsd:complexType name="heightWithUnits"> > <xsd:pattern> > <xsd:part type="xsd:decimal" /> > <xsd:part value="\p{Zs}*" /> > <xsd:part type="units" /> > </xsd:pattern> > </xsd:complexType> > > Input from Curt Arnold: > ---------------------- > Curt Arnold <carnold@houston.rr.com> to XML Schema Comments list, > Wed, 26 Apr 2000 07:56:59 -0500 > > The schema group stated that aggregate types were outside the > scope of the initial version. Derivation by list was a hard fought > exception to that principle. > If you are interested in discussions of dimensional units in XML, > I can send you URL's to quite a few discussions. > > Input from Martin Bryan <mtbryan@sgml.u-net.com>: > ------------------------------------------------- > "Martin Bryan" <mtbryan@sgml.u-net.com> to XML Schema Comments list > on Sun, 14 May 2000 08:01:08 +0100 > > The one area I still expect we are going to have problems in > using datatype for electronic commerce is measurements. > For example, how can I check that 100cm and 1m are exactly equivalent, > but 1yd is not. But again I do not expect you to have addressed > these problems at this state. > (Schema2 will be along within a few years!) > > Actual Resolution > ----------------- > > Discussed at Edinburgh Face to Face meeting. > We think it would be unwise to introduce secondary notations > for representing structures which can be represented > satisfactorily using XML. > > Explanation (by F. Olken) > ----------- > > Various versions of this issue were the subject of > considerable debate. The WG rejected the proposed changes > on the grounds that the requirement could be reasonably met > by use of some additional markup (in most cases), for example: > > <length> > <value> 5.25 </value> > <units> inches </units> > </length> > > The working group recognizes that such constructions > are not useable as single XML attributes. > > The WG was reluctant to go down the route of allowing further > grammatical structure within elements/arguments, allow the WG > felt obligated to preserve legacy composite structures such as > IDREFS, etc. > > Essentially, the Working Group felt that the existing XML > facilities could (largely) meet this requirement, and that > further elaboration of the language was undesirable, especially > in light of other comments we received that XML Schema Language > was already too baroque. > > Another reason for this reluctance is that the measurement > units application would eventually require more complex notations > such as: > > <density> 5 kg/(meter^3) </density) > > which would require more elaborate grammars. > > The measurement units application is dear to my heart, > and you are encourage to peruse the materials referenced > from the web page: > > http://pueblo.lbl.gov/~olken/mendel/units/units.htm > > for a more extensive treatment of how to encode measurement > units into XML. > > Is this response adequate ? > ------------------------------ > > We (XML Schema Working Group) want to know your opinion > of our response to your last call comments. This information > will be included with the package submitted to the W3C > Executive Director as part of the recommendation to take > the XML Schema Language to Candidate Recommendation. > We would appreciate your response as soon as possible. > > Please choose from one of the following responses, adding > whatever details, explanation you wish: > > 1) "Good enough" - You are satisfied with the Schema WG response > to your comments on XML Schema Language. The response meets > your requirements. The matter may be considered resolved. > > 2) "Stop the presses" - You are not happy with the response > to your comments on XML Schema Language. Either the response > is unclear or inadequate. The issue is of sufficient importance > and urgency that you want it called to the attention of the > W3C Executive Director and you ask that the XML Schema Language > delayed in advancing to Candidate Recommendation until the > issue is resolved. > > 3) "Later - Version 1.1" - You are not happy with the response, > but are prepared to defer reconsideration until XML Schema Lang. > Version 1.1 is drafted. It is anticipated (hoped) that Version 1.1 > will be completed by mid-2001. Version 1.1 is intended primarily > to fix small issues needed by other W3C Working Groups to proceed > with their work (especially XML Query Language). You request that > your comments be reconsidered when drafting the Version 1.1 > requirements document. > > 4) "Later - Version 2.0" - You are not happy with the response, > but are prepared to defer consideration until XML Schema Language > Version 2.0 is drafted. It is anticipated that Version 2.0 would > not be completed until late 2001 or early 2002. Version 2.0 may > include major revisions, e.g., multiple inheritance, etc. > You request that your comments be reconsidered when drafting the > Version 2.0 requirements document. > > 5) "No longer care" - You are not happy with the response, but > no longer care to pursue the matter, because .... > > Frank Olken > XML Schema Language Working Group > > Lawrence Berkeley National Laboratory (510) 486-5891 (voice) > Mailstop 50B-3238 (510) 486-4004 (fax) > 1 Cyclotron Road (510) 843-5145 (home) > Berkeley, CA 94720, USA (510) 442-7361 (pager) > > E-mail: olken@lbl.gov > WWW: http://www.lbl.gov/~olken/ -- Frank Olken Lawrence Berkeley National Laboratory (510) 486-5891 (voice) Mailstop 50B-3238 (510) 486-4004 (fax) 1 Cyclotron Road (510) 843-5145 (home) Berkeley, CA 94720, USA (510) 442-7361 (pager) E-mail: olken@lbl.gov WWW: http://www.lbl.gov/~olken/
Received on Thursday, 28 September 2000 20:40:21 UTC