basefinds(expression,sentence,factset,ruleset) → expressionlist
The basefinds subroutine takes as arguments an expression (called the aspect), a sentence (called the query), a dataset, and a ruleset. It uses the facts in the dataset and the rules in the ruleset (and only those facts and rules) to derive all instance of the query. It returns a list of all instances of the aspect for each query instance it finds; if it fails to derive any instances of the query, it returns [].
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Call: definefacts(repository,readdata('p(art,bob) p(bob,cal) p(bob,cam)'))
Exit: true
Call: definerules(library,readdata('g(X,Z) :- p(X,Y) & p(Y,Z)'))
Exit: true
Call: basefinds('Z',read('g(art,Z)'),repository,library)
Exit: [cal,cam]
Call: basefinds('X',read('g(art,cal)'),repository,library)
Exit: [art]
Call: basefinds(read('answer(X,Z)'),read('g(X,Z)'),repository,library)
Exit: [answer(art,cal), answer(art,cam)]
Call: basefinds(read('answer(X,Z)'),read('p(X,Y) & p(Y,Z)'),repository,library)
Exit: [answer(art,cal), answer(art,cam)]
Call: basefinds('Z',read('g(bob,Z)'),repository,library)
Exit: []
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The basefinds subroutine differs from compfinds in that it does not use the definitions of predefined functions and relations (except for same and distinct. Otherwise, they are equivalent.
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