dialect.pl -- Support multiple Prolog dialects

The idea for this predicate was raised by Vitor Santos Costa in a discussion to reach as a portability framework between SWI-Prolog and YAP.

This library defines :- expects_dialect/1, telling the system for which Prolog dialect was written, as well as useful tests in conditional compilation:

• exists_source/1
• source_exports/2

author

- Jan Wielemaker

- Vitor Santos Costa

See also

- if/1, require/1, term_expansion/2, goal_expansion/2.

 expects_dialect(+Dialect:atom) is det

Tell Prolog all subsequent code to the end of the file or the next :- expects_dialect/1 directive is written for the indicated Dialect. The current dialect is available through prolog_load_context/2.

To be done

- Should we setup the dialect module only as autoload for the current module?

 source_exports(+Source, +Export) is semidet

source_exports(+Source, -Export) is nondet

True if Source exports Export. Fails without error if this is not the case. See also exists_source/1.

To be done

- Should we also allow for source_exports(-Source, +Export)?

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 exists_source(Arg1)