43 lines
798 B
Plaintext
43 lines
798 B
Plaintext
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:- object(root, % avoid infinite metaclass regression by
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instantiates(root)). % making the class its own metaclass
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:- private(cv_/1).
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:- dynamic(cv_/1).
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:- mode(cv_(?integer), zero_or_one).
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:- public(cv/1).
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:- mode(cv(?integer), zero_or_one).
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:- public(set_cv/1).
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:- mode(set_cv(+integer), one).
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cv_(0). % cv_/1 value is stored locally, in this class
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cv(Value) :-
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cv_(Value). % retrive cv_/1 value, shared for all instances
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set_cv(Value) :-
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retractall(cv_(_)), % retract old cv_/1 value from this class
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asserta(cv_(Value)). % assert the new value into this class
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:- end_object.
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:- object(instance1,
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instantiates(root)).
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:- end_object.
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:- object(instance2,
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instantiates(root)).
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:- end_object.
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:- object(instance3,
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instantiates(root)).
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:- end_object.
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