negation by failureAn extralogical feature of Prolog and other logic programming languages in which failure of unification is treated as establishing the negation of a relation. For example, if Ronald Reagan is not in our database and we asked if he was an American, Prolog would answer "no".
Last updated: 1994-11-29
neep-neep ♦ negation by failure ♦ negative acknowledgement ♦ neighborhood bike code
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