| SAXONICA | 
Function signature
| $key-name | xs:string | 
| $key-value | xdt:anyAtomicType * | 
| Result | node() * | 
Returns the nodes identified by a named key declaration in the stylesheet.
Function signature
| $key-name | xs:string | 
| $key-value | xdt:anyAtomicType * | 
| $root-node | node() | 
| Result | node() * | 
Returns the nodes identified by a named key declaration in the stylesheet. The nodes selected are those that have a matching key-value, and that are within the subtree rooted at $root-node (which will generally be either a document node or an element)