CR: XML Path Language (XPath) 3.1

XML Path Language (XPath) 3.1

http://www.w3.org/TR/2015/CR-xpath-31-20151217/

feedback due by: 2016-01-31

Abstract


XPath 3.1 is an expression language that allows the processing of values conforming to the data model defined in [XQuery and XPath Data Model (XDM) 3.1]. The data model provides a tree representation of XML documents as well as atomic values such as integers, strings, and booleans, and sequences that may contain both references to nodes in an XML document and atomic values. The result of an XPath expression may be a selection of nodes from the input documents, or an atomic value, or more generally, any sequence allowed by the data model. The name of the language derives from its most distinctive feature, the path expression, which provides a means of hierarchic addressing of the nodes in an XML tree. XPath 3.1 is a superset of [XML Path Language (XPath) Version 3.0]. A list of changes made since XPath 3.0 can be found in I Change Log. The main new features in XPath 3.1 are:3.11.1 Maps. 3.11.2 Arrays.

A backwards compatibility mode is provided to ensure that nearly all XPath 1.0 expressions continue to deliver the same result with XPath 3.1; exceptions to this policy are noted in [H Backwards Compatibility with XPath 1.0].

Status of the Document


This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

This document is governed by the 1 September 2015 W3C Process Document.

W3C publishes a Candidate Recommendation, as described in the Process Document, to indicate that the document is believed to be stable and to encourage implementation by the developer community.

This document was jointly developed by the W3C XML Query Working Group and the W3C XSLT Working Group, each of which is part of the XML Activity. It will remain a Candidate Recommendation until at least 31 January 2016. The Working Groups expect to advance this specification to Recommendation Status.

This document will be considered ready for transition to Proposed Recommendation at the same time that the XQuery 3.1 specification is ready for transition to Proposed Recommendation.

Once the entrance criteria for Proposed Recommendation have been achieved, the Director will be requested to advance this document to Proposed Recommendation status. Working closely with the developer community, we expect to show evidence of implementations by approximately 1 March 2016.

This Candidate Recommendation specifies XPath version 3.1, a fully compatible extension of XPath version 3.0. The XML Query and XSLT Working Groups are publishing an updated version of this document because a number of changes were made as a result of review feedback; see the change log.

This specification is designed to be referenced normatively from other specifications defining a host language for it; it is not intended to be implemented outside a host language. The implementability of this specification has been tested in the context of its normative inclusion in host languages defined by the XQuery 3.1 and XSLT 3.0 (expected in 2015) specifications; see the XQuery 3.1 implementation report (and, in the future, the WGs expect that there will also be an XSLT 3.0 implementation report) for details.

This document incorporates changes made against the previous publication of the Working Draft. Changes to this document since the previous publication of the Working Draft are detailed in I Change Log.

Please report errors in this document using W3C's public Bugzilla system (instructions can be found at http://www.w3.org/XML/2005/04/qt-bugzilla). If access to that system is not feasible, you may send your comments to the W3C XSLT/XPath/XQuery public comments mailing list, public-qt-comments@w3.org. It will be very helpful if you include the string “[XPath31]” in the subject line of your report, whether made in Bugzilla or in email. Please use multiple Bugzilla entries (or, if necessary, multiple email messages) if you have more than one comment to make. Archives of the comments and responses are available at http://lists.w3.org/Archives/Public/public-qt-comments/.

Publication as a Candidate Recommendation does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by groups operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the XML Query Working Group and also maintains a public list of any patent disclosures made in connection with the deliverables of the XSL Working Group; those pages also include instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.