10. The computer program product of claim 9 , wherein the program instructions further comprise: program instructions to determine a subsume rule of the one or more subsume rules to apply based, at least in part, on an operation type of an incoming item of the one or more items and an operation type of a previous item of the subsumed update list.
9. The computer program product of claim 8 , wherein the program instructions to add the one or more items to the subsumed update list further comprise: program instructions to compare a first target node of a first item of the one or more items to a second target node of a second item of the second plurality of items, wherein the second item is a tail of the subsumed update list; and program instructions to, responsive to determining that the first target node is before the second target node in the document order: add the first item to the subsumed update list based, at least in part, on the document order and on the first target node; identify a non-attribute node by searching backwards through the subsumed update list from the tail; and apply the subsume logic to the first item and a preceding item in the subsumed update list, wherein the preceding item is associated with the non-attribute node.