23 lines
		
	
	
		
			478 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			23 lines
		
	
	
		
			478 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
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								:- object(proof_tree).
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									:- info([
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										version is 1.0,
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										date is 2004/5/2,
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										author is 'Paulo Moura',
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										comment is 'Meta-interpreter for pure Prolog.']).
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									:- public(solve/2).
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									:- mode(solve(+goal, -tree), zero_or_more).
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									:- info(solve/2, [
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										comment is 'Constructs a proof tree for a goal.',
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										argnames is ['Goal', 'Tree']]).
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									solve(true, true).
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									solve((A, B), (PA, PB)) :-
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										!, solve(A, PA), solve(B, PB).
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									solve(A, (A :- PB)) :-
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										clause(A, B), solve(B, PB).
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								:- end_object.
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