Understanding SGML and XML Tools

ion intended for the computer scientist or programmer rather than the user of SGML tools, and a detailed discussion of them would be outSide the scope of this book. There is extensive information about groves and their definition on the SGML Web site (http://www.sil. org/sgml /topi cs. html # groves) and in several books such as the one by DeRose and Durand already mentioned[17l, and in PractIcal Hypermedia [251 by Eliot Kimber. A graphical example of a fragment of a grove appears in Figure 64 In essence, a grove is an abstract representation of the model of what a parser should be able to 'see' once it has parsed a complete SGML document. It's what used to be called the 'parse tree', until it was realized that the tree is fractaleven an attribute value can be a tree[211 and a grove is really a group of such trees. A grove has been described as the 'in-memory result of parsing a document'[241. The SGML property set is the complete repertoire of objects and their properties that may occur in SGML, categorized into a number of classes. For any given document, the property set therefore defines the set of possible classes and their properties that each component can be allocated as it is