Re: How to return clause in findall/3

From: reader (no-spam_at_sonic.net)
Date: 08/14/04

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    Date: Fri, 13 Aug 2004 22:46:53 GMT

    Pere Montolio wrote:

    > In addition to the previous (and very nice) solution, you can also
    > test something like:
    >
    > clause2term(sc(A,B,C)) :- sc(A,B,C).
    >
    > followed by:
    >
    > findall(A,clause2term(A),L).
    >
    > (written without test: no visual prolog available).

       I like this idea better but I purposely omitted 'findall' because I
    am not sure it a good idea to expose Prolog newcomers to 'findall' early
    on.

       That said, SWI-Prolog allows

    clause2term(X) :- X.

    [ or clause2term(X) :- call(X). ]

    which allows

       clauses2list(Template,List) :-
         findall(Template,clause2term(Template),List).

       Given

    p(1).
    p(cat).
    p([mouse,mole,bird]).

    we have

    ?- clauses2list(p(_X),L).

    L = [p(1), p(cat), p([mouse, mole, bird])] ; 

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