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The Quintus meta_predicate/1
directive can in many cases be replaced by the transparent declaration.
Below is the definition of meta_predicate/1
as available from library(quintus).
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:- op(1150, fx, (meta_predicate)).
meta_predicate((Head, More)) :- !,
meta_predicate1(Head),
meta_predicate(More).
meta_predicate(Head) :-
meta_predicate1(Head).
meta_predicate1(Head) :-
Head =.. [Name|Arguments],
member(Arg, Arguments),
module_expansion_argument(Arg), !,
functor(Head, Name, Arity),
module_transparent(Name/Arity).
meta_predicate1(_). % just a mode declaration
module_expansion_argument(:).
module_expansion_argument(N) :- integer(N).
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The discussion above about the problems with the transparent
mechanism show the two cases in which this simple transformation does
not work.