Read XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition Online
Authors: Michael Kay
Simple mapping expressions use the convenient syntax of path expressions (that is, the
/
operator), but they work on atomic values rather than nodes. Specifically, the expression on the right-hand side of
/
must return a sequence that consists entirely of atomic values. For example, the expression
*/name()
returns a sequence of strings—the names of the child elements of the context node. There is no sorting into document order here, because document order doesn't mean anything for atomic values. The result is exactly the same as the expression
for $x in * return name($x)
, just with a more compact syntax.