... system^1.1

Many of the Prolog components of XSB are originally based on PSB-Prolog [53], which itself is based on version 2.0 of SB-Prolog [18].

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... interface,^1.2

InterProlog is available at www.declarativa.com/InterProlog/default.htm.

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... results).^2.1

This convention does not apply to the subdirectories of the examples directory, which illustrate advanced features of XSB.

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... symbols ^3.1

Operator symbols can be exported as any other symbols, but their precedence must be redeclared in the importing module.

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...usermod^3.2

The standard predicates of XSB are listed in $XSB_DIR/syslib/std_xsb.P.

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... XSB^3.3

Any parallelisation directives (parallel) are simply ignored by the compiler, but do not result in syntax errors to enhance compatibility with various other earlier versions of PSB-Prolog.

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... systems^3.4

The most common uses of mode declarations in Prolog systems are to reduce the size of compiled code, or to speed up a predicate's execution.

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... factoring:^3.5

Unification factoring was once called transformational indexing, hence the abbreviation ti in the compiler directives

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...C^5.1

We use the term ``answer set'' to describe the set of answers associated with a given subgoal during a given state of computation. As such, it has no relation to the use of the term ``answer set'' in the non-monotonic literature.

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... HREF="node72.html#sec:table-aggregation">5.4^5.2

We also note that the library subsumes contains routines for checking variance and subsumption.

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... aborted^5.3

A more sophisticated solution is proposed in [46].

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... release^6.1

We also note that the ISO Prolog evaluable functors sign/1, float_round/1, float_truncate/1, float_integer_part/1 and float_fractional_part/1 are not implemented in Version 2.5.

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... module^6.2

The only limitation is that blah must indeed be a module in the sense that it exports at least one symbol.

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... 0}.^9.1

A term like

{foo} is just a syntactic-sugar for the term

'{}'(foo).

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... brackets.^9.2

Readers familiar with Quintus Prolog may notice the difference in the treatment of the various kinds of not. For example, in Quintus Prolog a not/1 that is not enclosed within curly brackets is interpreted as a non-terminal grammar symbol.

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