[PPL-devel] Re: [Xsb-development] x still a variable after a successful call to c2p_list(x) (2nd attempt)

Bart Demoen wrote:

should be easy to fix: seems like is_var does not deref

I have checked: none of the is_*() functions seems to dereference. However, other interface functions do dereference.

Notice also that, while cinterf.h contains the declaration of p2p_deref() along with the rather obscure comment

** p2p_deref: prolog_term -> prolog_term !! uncommon

p2p_deref() is never mentioned in the XSB manuals.

So the questions are: how is one supposed to use the foreign language interface? Calling p2p_deref() before any invocation of is_*()? Are there other interface functions that require the client code to call p2p_deref() for proper operation?

All the best

Roberto