extends_category(Category1, Category2) extends_category(Category1, Category2, Scope)
Enumerates, by backtracking, all pairs of categories such that the first one extends the second. The relation scope is represented by the atoms public
, protected
, and private
.
extends_category(?category_identifier, ?category_identifier) extends_category(?category_identifier, ?category_identifier, ?scope)
type_error(category_identifier, Category1)
type_error(category_identifier, Category2)
type_error(scope, Scope)
| ?- extends_category(basic, Category). | ?- extends_category(Category, extended, private).