15. The non-transitory computer readable storage medium of claim 13 , wherein each set of node types of the mapping is an ordered set and the order of the identified set of node types is determined based on an order in which node types are encountered during a traversal from the root node to the selected node.
15. The non-transitory computer readable storage medium of claim 13 , wherein each set of node types of the mapping is an ordered set and the order of the identified set of node types is determined based on an order in which node types are encountered during a traversal from the root node to the selected node. 16. The non-transitory computer readable storage medium of claim 15 , wherein identifying a set of handlers mapped to the identified set of node types comprises: selecting a matching set of node types in the mapping such that the order of the node types of the matching set matches the order of the node types of the identified set; and selecting the set of handler mapped to the matching set of node types.