The Watson system that you mentioned, like many other NLP systems, has been developed in accordance with the ISO SICStus Prolog . In its latest version 4.3, SICStus contains a JIT compiler, which is enabled by default and works completely transparently. The properties of the predicate jittableand jittedare the only way to see that jitter is present - with the exception of performance improvements. Besides the basic functionality of ISO, SICStus offers freeze/2, and dif/2since 1985; with CLP (Q) and CLP (FD) added a few years later. The only drawback of SICStus is its
price .
SWI-Prolog , . SWI7 ISO , Prolog Prolog (Marseille) DECsystem 10 Prolog () .
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