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InstanceOf

InstanceOf::class[object]
checks, if object was generated by means of class or a class derived directly or indirectly from class. The object must have been generated by New.
  • While TypeOf tests classes, InstanceOf tests objects.
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Basic Examples   (1)
This loads the package.
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The next cell generates a tiny class hierarchy. The class child demonstrates a typical usage of InstanceOf.
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We generate for each class an object by applying Dot to New and the class' constructor.
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As expected, obj and parent are accepted by f, because they do have base in their class hierarchy, while alien does not match.
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The check can also be applied directly.
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Any other "class" yields False.
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Please observe that the ::-operator acts on the scond argument rather quickly. Therefore, the following fails.
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