A Prolog variant with guarded clauses and committed-choice nondeterminism (don't-care nondeterminism) by Ehud "Udi" Shapiro, Yale <firstname.lastname@example.org>. A subset has been implemented, but not the full language.
See also Mandala.
["Concurrent Prolog: Collected Papers", E. Shapiro, V.1-2, MIT Press 1987].
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Nearby terms: Concurrent Object-Oriented Language « Concurrent Pascal « concurrent processing « Concurrent Prolog » Concurrent Scheme » ConcurrentSmalltalk » Concurrent SP/k