A list, or other Lisp object accepted for some layout class.
The generic function
interpret-description is used by the layout mechanism to translate an abstract description of
's children (supplied by the initarg
(setf layout-description)) into a list of objects to actually use. Each object must be either an element (an object of type simple-pane or of type pinboard-object) or a geometry object (the result of the default method of parse-layout-descriptor).
The default method specialized on layout expects description to be a list, and returns a list of the values returned by parse-layout-descriptor for each element. Some built-in subclasses of layout have their own methods, which allow different values of description . In these cases the manual page for the layout class describes what the description can be.
For example, column-layout expects as its description a list of items where each item in the list is either the slot-name of the child or a string which should be turned into a title pane. This is the default handling of a layout's description, which is done by calling the generic function parse-layout-descriptor to do the translation for each item.
CAPI User Guide and Reference Manual (Unix version) - 3 Aug 2017