Diff operations can be grouped together and form an extended operation. Each extended operation has an ID number, and all the related XML Diff operations carry this number in their opid attribute. The extended operation also has a descriptor that further describes the operation.
For example, a move operation is considered an extended operation. It consists of two types of operations; one remove operation and one add operation. Both of these operations are indicated in the XDL Diffgram in the places where the nodes have been removed and added. The same ID number connects these two operations together with the operation descriptor, and indicates that the remove and add pair are in fact a move operation.
The descriptors of the extended operations appear as elements named
xd:descriptor. The following table describes the mandatory attributes of all the
|Attribute name||Data type||Description|
|opid||unsigned int||Operation ID.|
|type||string||Type of the descriptor.|
XML Diff Functionality | Running Comparisons Between Documents, Fragments, or Nodes | Setting Options that Affect the Comparison | Selecting the Algorithm for the Comparison | Limitations | XML Diff Language (Diffgram) | Path Descriptors | Example of a Diffgram |XmlDiff Class