This data model defines a property called Base URI that is associated with a document node and with every element node. In an ideal world, the value of this property will conform with the [XML Base] Recommendation.
Section 7.6.2 base-uri Accessor defines an accessor dm:base-uri representing the Base URI property of a node.
Note:
The Base URI property of a document node that derives from parsing an XML document at some location typically indicates the location from which the document was retrieved. For a document node constructed by a query or stylesheet, it is generally derived from the base URI of the query or stylesheet.
The Base URI property of a document node that derives from parsing an XML document at some location typically indicates the location from which the document was retrieved. For a document node constructed by a query or stylesheet, it is generally derived from the base URI of the query or stylesheet. The base URI property of element nodes may vary from that of the containing document node: the most common reasons for this are (a) that parts of the document may derive from parsing of XML external entities at different locations, and (b) the Base URI property may be explicitly set using an xml:base attribute.The base URI property of element nodes may vary from that of the containing document node. The most common reasons for this are (a) that parts of the document may derive from parsing of XML external entities at different locations, and (b) the Base URI property may be explicitly set using an xml:base attribute.The Base URI property of a document node that derives from parsing an XML document at some location typically indicates the location from which the document was retrieved. For a document node constructed by a query or stylesheet, it is generally derived from the base URI of the query or stylesheet. The base URIbase URI property of element nodes may vary from that of the containing document node: the. The most common reasons for this are (a) that parts of the document may derive from parsing of XML external entities at different locations, and (b) the Base URI property may be explicitly set using an xml:base attribute.
The Base URI property of a document or element node may be absent, indicating that no value for the property is known. This can happen, for example, when a document is constructed by parsing a stream of characters or octets that is not associated with any known location.
It is also possible that the algorithm defined in [XML Base] for computing a base URI fails to deliver a valid URI. This can arise for various reasons: many software products that construct representations of XML documents are liberal in what they accept; some even pre-date the [XML Base] Recommendation. The [Infoset] Recommendation itself acknowledges the concept of “synthetic infosets” that do not adhere to all defined constraints. Pragmatically, this specification therefore acknowledges the possibility of a third state: the base URI of a document or element node is either a valid URI, or it is absent, or it may be invalid. The accessor dm:base-uri when applied to a node may therefore deliver either a URI, or the special value absent, or it may raise an error indicating that the value is invalid. In an ideal world, the value of the Base URI property will conform with the [XML Base] Recommendation. It is possible, however, that the algorithm defined in [XML Base] for computing a base URI fails to deliver a valid URI. This can arise for various reasons: many software products that construct representations of XML documents are liberal in what they accept; some even pre-date the [XML Base] Recommendation. The [Infoset] Recommendation itself acknowledges the concept of “synthetic infosets” that do not adhere to all defined constraints. Pragmatically, this specification therefore acknowledges the possibility of a third state: the base URI of a document or element node is either a valid URI, or it is absent, or it may be invalid. The accessor dm:base-uri when applied to a node may therefore deliver either a URI, or the special value absent, or it may raise an error indicating that the value is invalid. If the Base URI property of a node is invalid, then operations that depend on the Base URI (the most obvious example being the fn:base-uri function) may raise a dynamic error. In an ideal world, the value of the Base URI property will conform with the [XML Base]It is also possible Recommendation. It is possible, however, that the algorithm defined in [XML Base] for computing a base URI fails to deliver a valid URI. This can arise for various reasons: many software products that construct representations of XML documents are liberal in what they accept; some even pre-date the [XML Base] Recommendation. The [Infoset] Recommendation itself acknowledges the concept of “synthetic infosets” that do not adhere to all defined constraints. Pragmatically, this specification therefore acknowledges the possibility of a third state: the base URI of a document or element node is either a valid URI, or it is absent, or it may be invalid. The accessor dm:base-uri when applied to a node may therefore deliver either a URI, or the special value absent, or it may raise an error indicating that the value is invalid. If the Base URI property of a node is invalid, then operations that depend on the Base URI (the most obvious example being the fn:base-uri function) may raise a dynamic error.