More on XPath

• XPath is actually much more than this simple path-based notation: it can define expressions for lists based on value criteria, including attribute values, and has two complete syntaxes, a compact one we just used in the example, and a more generic one.
  • Here is a more elaborate example:

    descendant::*[attribute::*!='2.0']

    This expression selects all nodes descending from a node having at least one attribute with a value not equal to "2.0".
  • XPath expressions are namespace-aware:

    /wsdl:definitions/wsdl:message[@name=substring-after($message, ':')]/wsdl:part

    as in this example from an XSLT transform presenting a WSDL web service contract in XHTML format
• Warning: whitespace and line feeds are significant in XPath, unlike most usual languages (but like regular expressions)..
• A non official, but very convenient reference is available at http://www.mulberrytech.com/quickref/