If the native double type of the DOM binding does not directly support the exact IEEE 754 result of the XPath expression, then it is up to the definition of the binding to specify how the XPath number is converted to the native binding number.
Returns the indexth item in the snapshot collection.
If index is greater than or equal to the number of nodes in the list, this method returns null. Unlike the iterator result, the snapshot does not become invalid, but may not correspond to the current document if it is mutated.
Index into the snapshot collection.
The node at the indexth position in the NodeList, or null if that is not a valid index.