21. The computing device of claim 20 , wherein means for storing at least a portion of the generated DOM tree in a key-value data structure comprising means for storing at least a portion of the generated DOM tree in a hash-map data structure.
21. The computing device of claim 20 , wherein means for storing at least a portion of the generated DOM tree in a key-value data structure comprising means for storing at least a portion of the generated DOM tree in a hash-map data structure. 22. The computing device of claim 21 , wherein means for retrieving previously stored calculations from the memory comprises means for evaluating hash-keys associated with nodes of the stored DOM tree that are isomorphic with the portion of the generated DOM tree.