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Text File | 1989-10-20 | 932 b | 25 lines | [TEXT/GEOL] |
- Item 9336129 18-Oct-89 10:05
-
- From: D0220 American Zettler, Dirk Tjossen,PRT
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- To: MACAPP.TECH$ MACAPP Tech
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- Sub: Object Casting Clarification
-
- I have studied this topic endlessly and now admit I need assistance. In the MPW
- Pascal manual (p.222), it states:
- "Which particular version of an overridden method is executed
- when a method call is executed depends on the type of the object,
- not the type of the reference variable."
-
- Yet the TSortedList.Compare method override example in MacApp Version 2.0ß9
- release manual (MacApp 2.0 Feature Overview, pp.7-8) expressly states:
- "Note that item1 and item2 must be cast from type TObject to
- their actual type."
-
- The two references seem to be contradictory. Why would a cast be required in
- the TSortedList example? What subtle point(s) am I missing here?
-
- Dirk A. Tjossem
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-