Prolog Visualizer

Prolog VisualizerTutorial

Visualization

Program

Controls

Examples

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This is where you start

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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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Unifying

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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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These rules failed too

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But not this rule

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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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Unifying

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This rule also succeeds

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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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Unifying

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Succeeded

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This leads to a solution

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Backtrack

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More solutions…

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…