Earlier? I wrote the patch hours before you noticed it. I was just another iteration of wishing outloud for that feature we've talked about before but have now. There are some major deficiencies with my patch. I think I need to call your unify function but didn't. I think that the normal perlcall/2 should only succeed and call the perl function if all the variables are bound. I think I made a mess of converting your Terms back into perl data. I did something that worked but I didn't understand your organization (you didn't document it!) and probably got it wrong. The current perlcall2/2 searches upwards through the call stack to find the function named X. That should probably be saner - maybe introduce a perlpackage/1 builtin. Maybe tell perlcall2/2 how to tell the difference between fully qualified function names and relative names. There should be a perlmethod2/2 as well to support method calls. Yes?

Much of this can be experimented with once there's a few builtins for looking back at perl.

perlcall(X,Y) :-
    boundp(X), % uh... a predicate for asking that X need no further u
+nification so perlcall only gets complete answers
    boundp(Y),
    perlcall2(X,Y),
    !.
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