creating choice points without Pl_Query_Begin

[Bowie Owens]

Hi everyone,

I was wondering if there is a way to create choice points without using 
the Pl_Query_ functions. I have been trying to implement backtracking 
search within Java using nested queries. However, I hit the limit on the 
query stack size.

// create a choice point to which I can undo everything underneath
gprolog.Pl_Query_Begin(gprolog.TRUE);
int[] arg = { };
gprolog.Pl_Query_Call(gprolog.Find_Atom("true"), 0, arg);

// some code which posts some constraints cutting after each post, may 
succeed or fail

if (success)
   gprolog.Pl_Query_End(gprolog.PL_CUT);
   // continue
else {
   gprolog.Pl_Query_End(gprolog.PL_RECOVER);
   // goto try next value
}
                
Create_Choice_Point and Delete_Choice_Point look like just the thing. 
Except I don't know what to pass for the codeptr and how to do the cut. 
Any help would be appreciated.

FYI gprolog 1.2.17, swig 1.3, java 1.4.2.

--
Bowie Owens

CSIRO Mathematical & Information Sciences
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