XLink Markup Design
This section describes the design of XLink's markup vocabulary.
Link markup needs to be recognized reliably by XLink applications in order to be traversed and handled properly. XLink uses the mechanism described in the Namespaces in XML Recommendation [xname] to accomplish recognition of the constructs in the XLink vocabulary.
The XLink namespace defined by this specification has the following URI:
http://www.w3.org/1999/xlink
As dictated by [xname], the use of XLink elements and attributes requires declaration of the
XLink is concerned with linking itself, as the term is understood in the hypertext community: establishing (non-sequential) connections between data objects. This is distinct from addressing mechanisms such as URIs and XPointers: A URI is not properly speaking a link, just as an HREF attribute is not an A element. The XLink specification is intended to enable:
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Identifying linking elements beyond A and IMG;
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Attaching links to documents without modifying them (annotations, "stand-off" tagging, etc.);
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Providing external, symmetrical,
The XML Namespaces Recommendation seems to be causing a great deal of confusion. This note attempts an alternative explanation of the mechanism described in the Recommendation which I hope will be less confusing.
In the data model implied by XML, an XML document contains a tree of elements. Each element has an element type name (sometimes called the tag name) and a set of attributes; each attribute consists of a name and a value. Applications typically make use of the element type name and attributes of an element in determining how to process the
This document specifies XML syntax and processing rules for creating and representing digital signatures. XML Signatures can be appliedto any digital content (data object), including XML. An XML Signature may be applied to the content of one or more resources.Enveloped or enveloping signatures are over data within the same XML document as the signature; detached signatures are over data external to the signature element. More specifically, this specification defines an XML signature element type and an XML signature application; conformance requirements
Unlike its companions XLink and XML Base, XPointer has retreated from Candidate Recommendation to Last Call Working Draft status.
Daniel Veillard noted that:
"This second Last Call has been made necessary by a change required to XPointer to insure that URI References built using XPointer are context independant. This specific addition is detailed in section 5.2.1 of this XPointer Working Draft."
The problem appears to revolve around namespaces, as the spec now adds:
"For any XPointer part that uses the xpointer scheme, the evaluation context