The XSL Working Group is chartered to continue the developement of XSL (extensible stylesheet language), a style sheet and transformation language for XML and other structured markup languages.
The overall goal of this work is to define a practical style and transformation language capable of supporting the transformation and presentation of, and interaction with, structured information (e.g., XML documents) for use on servers and clients. The language is designed to build transformations in support of browsing, printing, interactive editing, and transcoding of one XML vocabulary into another XML vocabulary. To enhance accessibility, XSL is able to present information both visually and non-visually. XSL is not intended to replace CSS, but will provide functionality beyond that defined by CSS, for example, element re-ordering.
The intent of the XSL effort is to define a style specification language that covers at least the formatting functionality of both CSS and DSSSL. The intent is also that within XSL, the formatting properties and values of CSS can be used with their current meaning. Where the functionality of CSS and XSL overlap, the style information shall be exportable in both XSL and CSS. As the XSL activity goes forward, the formatting model will be extended as a joint effort of the CSS and XSL working groups.
XSL is constituted of three main components, a transformation language known as XSLT, an expression language for addressing parts of XML documents, known as XPath, and a vocabulary of formatting objects with their associated formatting properties, known as XSL-FO.
This charter defines the second phase in the development of XSL. Both XSLT Version 1.0 and XPath Version 1.0 were published as W3C Recommendations in November 1999. Formatting objects are currently described in a working draft in last call processing.
The XSL WG will move this specification of formatting objects to Proposed Recommendation, thus terminating the work on XSL 1.0. It will also do maintenance work for this first version of XSL.
[update (February 2002): When this WG was chartered in June 2000, formatting objects were described in a Working Draft in last call processing. The XSL WG moved this specification of formatting objects to Recommendation on 15 October 2001, thus terminating the work on XSL 1.0.]
The WG will also develop the next version of XSL, including new versions of XSLT and XPath as well as extensions to formatting objects and their properties. The goal is to cope with the requirements that are not addressed yet by the first version.
Features under consideration for XSLT and XPath are an expanded extension mechanism as well as other requirements mentioned in appendix G of XSLT version 1.0. XML schemas have also to be taken into account.
Formatting objects will be developed providing additional support of internationalized formatting objects, such as ruby and kendot, general regions and other requirements that will come from the implementers and users of version 1.0.
The XSL WG will be considered successful when it progresses version 1.0 of XSL to Recommendation and then produces a new version of XSL, including enhanced XSLT and XPath languages as well as advanced formatting objects that address requirements that are not covered by version 1.0.
The primary deliverables of the XSL WG under this charter are:
As XSLT 1.0 and XPath 1.0 have already been published, the main part of this document is a specification of formatting objects and properties
Note that it is anticipated that there will be some joint development and coordination with the XML Query WG on issues related to compatibility and extensions.
The public release of each technical document has to be approved by the working group. The Chairs determine consensus for publication. Minutes are published under the Chairs responsibility.
The XSL Working Group is proposed to begin work in June 2000 and to continue for 21 months, terminating in February 2002 after the publication of the next version of XSL and XSLT/XPath as W3C Recommendations.
The following documents will be published by the XSL WG, in that order:
This group was planned to last for 21 months, following its approval by W3C members. The charter commenced in June 2000 and was originally supposed to expire in February 2002. It was extended by the Director's decision until December 2002 to finish remaining work.
Liaison with the CSS group in the areas of Web stylesheet requirements is necessary in order to ensure that the market develops in a planned and unified fashion. In particular, the formatting model will be extended as a joint effort of the CSS and XSL working groups.
The XSL WG will cooperate with the Web Accessibility Initiative (WAI) to ensure XSL meets W3C accessibility goals. The WAI WG will provide expertise for work in this area and will review the specifications produced by the XSL WG.
Extension of formatting objects to support non-Western languages will need the expertise of the I18N WG. In addition, the I18N WG will be solicited to comment on the new features added to XSLT, and check that they can be used to transform documents written in any language.
The XPath expression language is part of the XSL specification and was developed by the XSL WG in cooperation with the XML Linking WG. It is now an input to the XML Query WG. It is anticipated that there will be significant liaison and cooperation between the XML Query WG and the XSL WG to address issues related to compatibility of XML Query with XPath and XSLT.
The Math WG has developed a presentation language for mathematical expressions, as part of the MathML specification. To address the specific requirements of mathematical text formatting, the XSL WG will have liaison with the Math WG and take advantage of their expertise in that field.
As part of the HTML activity, a specification for extended forms (XForms) is under development. The XSL WG will have to consider how to handle these elements in combination with the XSL formatting objects. Cooperation with the XForms WG will be needed for that purpose.
The XSL WG participates in both the Hypertext CG and the XML CG. The XSL WG is represented in these CGs by its Chairs or by a WG member appointed by the Chairs.
The XSL WG is responsible for maintaining active communication with national and international standards bodies and industry consortia whose scope of work intersects its own. This specifically includes, but is not limited to, ISO/IEC JTC1/WG4, the national bodies corresponding to WG4 (insofar as practical), Oasis, and IETF.
The XSL WG will work with other W3C WGs to determine the appropriate media type registration for XSL.
The level of participation expected of XSL WG members requires that they be experts in composition, typography, computer display rendering, or computer language design. Additionally, they must support the purpose of the WG set forth in Section 1 of this charter; that they be willing and able to devote at least 15 percent of their working time to the activity, including participation in regular phone conferences and face-to-face meetings.
The expertise of prospective WG members shall be determined by the WG Chairs. Alternates (defined below) must meet the same level of expertise required of principals.
When joining the XSL WG, participants must disclose IPR claims according to W3C's IPR policy.
The co-chairs of the XSL WG are Sharon Adler (IBM) and Steve Zilles (Adobe).
Principal members of the WG may be representatives of the W3C staff, W3C member organizations or invited experts.
For each principal WG member who represents the W3C or a W3C member organization, there may be another person representing that organization (called an alternate member) who is allowed to substitute for that organization's principal representative when the principal is temporarily unable to attend a WG conference. Attendance by an alternate discharges the principal's attendance obligations. Alternate members may also participate in the WG mail list, and in the teleconferences, and they are entitled to attend face-to-face meetings, but they may not vote in those meetings except when standing in for their principal. Except for attendance requirements, alternate representatives must meet the same criteria as principal representatives and are formally approved by the same process.
WG phone conferences are held every week. When necessary to meet agreed-upon deadlines, phone conferences may be held twice a week. Participation in phone conferences is limited to principal members or, in the case of members representing W3C member organizations or W3C staff, alternates acting in their stead. Principals may allow alternates to participate in phone conferences and may yield the floor to their alternates with the permission of the Chairs. The Chairs may, at their discretion, invite interested observers to attend particular phone conferences if their input is needed on particular questions.
Face-to-face meetings are three-day sessions held at most six times per year. To maximize liaison between the WG and relevant standards bodies and vendor organizations, scheduled face-to-face meetings may be held in conjunction with major industry events and standards meetings.
All face-to-face meetings are announced on the XSL WG page as well as on the Member calendar.
Participation in face-to-face meetings is limited to principal members, formally approved alternates, and individual experts invited by the WG Chairs. Invited experts who have not been formally approved as WG members have observer status and may not take part in voting. Formal votes taken during face-to-face meetings follow the procedure specified in Section 7 below. In such votes, the single vote that can be cast by any W3C staff member or W3C member organization represented on the WG is cast by the principal member representing that organization if the principal is present or, if not, by that principal's alternate if the alternate is present.
XSL WG members communicate via an archived mailing list, w3c-xsl-wg, visible to all W3C members. During their development, all working documents are available to the XSL WG and W3C members. They are posted on the XSL WG area of the W3C server.
This charter shall be publicly accessible on the W3C Web site.
Communication with the public is achieved by publishing new versions of working drafts at least every 3 months and through a public mailing list.
The W3C Team shall provide a contact person to participate as a principal member of the WG and may provide an alternate member as well. W3C members are expected to maintain the same level of participation as other principal members.
The Group works by consensus. In the event of failure to achieve consensus, the Group may resort to a vote as described in the Process Document.