Built-in Classes

ACEDB includes several models which are used by the system to perform various tasks. The system models are not found in wspec, cannot be changed by the curator, and will be visible even if the database has been initialized with an empty models.wrm.

Some examples already discussed are ?Keyword and ?Text. ?Comment is another class with similar properties. Others system classes are used for table definitions (?Table and ?Table_definition), display colors (?Colour), display configuration (?View) and session control (?Session). The screen dump shows how these appear in a reinitialized database with an empty models.wrm.

The Keyset class by default is available from the main window. Keysets are simply lists of object names, as might be returned by a query or displayed in the main keyset window when a class is browsed. They can also be entered as data by the curator via ordinary text files, in which they are specified in a "class-object" format. A simple example is

KeySet "My favorite T-shirts" 
TShirt Sam22 
TShirt Sam18
Tshirt Sam37