17 lines
281 B
Text
17 lines
281 B
Text
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:- object(singleton).
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:- public(value/1).
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value(Value) :-
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state(Value).
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:- public(set_value/1).
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set_value(Value) :-
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retract(state(_)),
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assertz(state(Value)).
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:- private(state/1).
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:- dynamic(state/1).
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state(0).
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:- end_object.
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