Prolog VisualizerTutorial
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Initial goal A copy of the program
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Dashed box indicates the current state of the search
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Unification failed because the names of the clauses are different
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Failed rules are crossed out
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substitutionbefore
after
Applying the substitution, you get a new rule
This rule unifies with the goal
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Current goal is duplicated here for better readability
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Body of the rule after substitution
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grandfather(X, Y) is replaced by father(X, Z)
and father(Z, Y). these are the new goals
Current state has changed
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The grey path shows where you came from
current goal is in bold
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This is a partial solutionIf X is orville, any Y such that
father(abe, Y) will be a solution
father(Z, Y) is the is new goal. After the substitution (X = oriville, Z = abe), it
becomes father(abe, Y)
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Current state has changed
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