#!/usr/bin/env swipl % % PFC is a language extension for prolog.. there is so much that can be done in this language extension to Prolog % % Dec 13, 2035 % Douglas Miles % was_module(sanity_if_missing_02,[]). :- include(test_header). :- dynamic((foob/1,good/0,if_missing/2)). :- begin_pfc. (if_missing(Missing,Create) ==> ( ( \+ Missing/(Missing\=@=Create)) ==> Create)). :- set_prolog_flag(gc,true). good ==> if_missing(foob(_),foob(a)). good. :- mpred_test(foob(a)). % :- break. \+ good. :- sanity(\+ good). :- listing(foob/1). :- mpred_test(\+foob(a)).