If the attribute axis is used and the NodeTest is a NameTest (for example, @title , @* , or @svg:* ), then we are looking for an attribute node.
If the attribute axis is used and the NodeTest is a KindTest (for example, @schema-attribute(xml:space) ), then we are looking for nodes on the attribute axis. Of course, the only nodes found on the attribute axis are attribute nodes. The patterns @comment() and @text() are not illegal, but they are pointless, because the attribute axis cannot contain comments or text nodes. However, the NodeTest @node() looks for any node on the attribute axis, so it is equivalent to @* .