12 lines
254 B
Plaintext
12 lines
254 B
Plaintext
# Derive ancestors from parent relationships.
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fact Parent(alice, bob).
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fact Parent(bob, carol).
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fact Parent(carol, dave).
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rule Parent(?X, ?Y) -> Ancestor(?X, ?Y).
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rule Ancestor(?X, ?Y), Parent(?Y, ?Z) -> Ancestor(?X, ?Z).
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run.
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query Ancestor(?X, ?Y)?
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