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The New DDL Specification

Each DDL definition is enclosed in a STAR save frame cell. gif A save frame cell is named according to a rule where a category identifier and an optional item identifier are combined to uniquely identify a cell. The term identifier and its abbreviation id are used to refer to the two components of the full STAR item name. The term name is used to identify a complete STAR specification of a data item. The save frame cell is closed with an unnamed save_ token.

For data item definitions, the category and item identifiers separated by a period form the save frame identifier, and the save frame identifier preceded by an underscore character forms the full STAR data item name. For category definitions, the category identifier alone is used as the save frame identifier. The syntax of the definition within a save frame cell follows the STAR grammar defined in reference [5]. The following abbreviated example illustrates this for the definition of the hypothetical item item_a in category category_1.

           save__category_1.item_a

               _item.name           '_category_1.item_a'

           save_

In this example, the data item _item.name is assigned the value _category_1.item_a which is the name of the item to which this definition applies.



John Westbrook
Thu Apr 11 06:25:55 EDT 1996