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Inheritance mechanism of type-level attributes

As already said, a new type definition could override the values of some of the attributes of the supertype. The new values, though, might still bear some relation with the ones in the supertype. This has led to the definition of a few different inherintance semantics. The inher field specify how the new value of the declared attribute relates to the one in the supertype. It can assume one of the following values (see 1.5 also):

  
Figure 1.5: Inheritance mechanism.



Passani Luca
Mon Feb 20 21:59:27 MET 1995