Sather - Language Specification Prev Chapter 4. Code inclusion and include clauses Example 4-8.
Implementation inheritance is defined by include clauses .
The include clause may begin with the keyword ' private ', in which case any unmodified included feature is made private. We say that there is an include path from one type to another if there is a sequence of types between them such that each includes the next in the sequence. Partial classes may be included. There must be no cycle of classes such that each class includes the next, ignoring the values of any type parameters but not their number. In this case, the listed features are included as part of the public interface unless they are specified as ' private ' or ' readonly '.