The ListOf command enables you to specify that a property contains a list of other objects - diagrams, symbols, or definitions. For example, a Class contains a property called Attributes, which is a list of class attributes. Class attribute is a definition type in of itself, which has its own set of properties. The object type referenced must have been defined already in SAPROPS.CFG or at the top of the USRPROPS.TXT file.
Contrast the ListOf property to simple textual list. Elements in the ListOf list increase as users add definitions to the repository; for a simple list the number of elements in the list presented to the user is static (based on the LIST statement at the head of the USRPROPS.TXT file).