Re: Passing a list as a argument via C

So, problem solved.
It seems like Prolog is very sensitive to how the string representing the
list is formatted (it comes from a Python script). I had to remove single
quotes and trim every entry, then it worked.
Thank you anyway!


2013/7/22 Emanuele Bastianelli <[email protected]>

> Hi to all,
>
> I've a little problem with my C interface to Prolog.
> I need to pass a list as an argument to my Prolog query, and i tried to
> use PlTail but it didn't work.
> This is my code:
>
> PlTermv argomentiVar((int)req.arg.size());
>
> for(int i=0; i<(int)req.arg.size(); ++i){
>     if (req.arg[i][0] == '[')
>     {
>
>        PlTail list(argomentiVar[i]);
>         string substring = req.arg[i].substr(1,req.arg[i].length()-2);
>         char* tokens = strtok((char *)substring.c_str(), ",");
>         while(tokens != NULL) {
>         list.append(tokens);
>         tokens = strtok(NULL,",");
>
>     }
>     list.close();
>     }
> }
>
> PlString PlS = PlString(req.predicate.c_str());
> PlQuery eF(PlS, argomentiVar);
>
> I want PlTail to be an argument of tipe list, as for the query eF, for
> example [a,b,c,d].
>
> Thank you
>
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