A.43 library(prolog_xref): Prolog cross-referencer data collection
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Availability::- use_module(library(prolog_xref)).(can be autoloaded)
Source[semidet]xref_meta(+Source, +Head, -Called)
True when Head calls Called in Source.
Called is a list of called terms, terms of the form Term+Extra or terms of the form //(Term).