XSB

XSB is the name of a dialect of the Prolog programming language and its implementation developed at Stony Brook University in collaboration with the Katholieke Universiteit Leuven, the New University of Lisbon, Uppsala University and software vendor XSB, Inc.Originally, XSB was an extended version of SB Prolog, developed at Stony Brook. It was initially called XSB Prolog, but its developers decided to drop the Prolog in the name.XSB extends Prolog with tabled resolution and HiLog (a standard extension of Prolog permitting limited higher-order logic programming).
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XSB extends the standard functionality of Prolog (being a descendant of PSB- and SB-Prolog) to include implementations of OLDT (tabling) and HiLog terms. OLDT resolution is extremely useful for recursive query computation, allowing programs to terminate correctly in many cases where Prolog does not. HiLog supports a type of higher-order programming in which predicate symbols can be variable or structured. This allows unification to be performed on the predicate symbols themselves in addition to the arguments of the predicates. Of course, Tabling and HiLog can be used together.
Version 1.2
ports: Sun, Solaris, NeXT, Linux, 386 BSD, IRIX, HP-UX
portability: Generally to 32-bit machines.
interpreter, preprocessor(HiLog), documentation
XSB research group / SUNY at Stony Brook
ftp://sbcs.sunysb.edu/pub/XSB/XSB.tar.Z.
(130.245.1.15) E-mail: xsb-contact@cs.sunysb.edu.
(1993/07/28)