99 lines
1.8 KiB
C++
99 lines
1.8 KiB
C++
#include <Rcpp.h>
|
|
|
|
#undef Realloc
|
|
#undef Malloc
|
|
#undef Free
|
|
#include <yapi.hh>
|
|
|
|
#include <vector>
|
|
#include <string>
|
|
|
|
#include "real.h"
|
|
|
|
|
|
using namespace Rcpp;
|
|
|
|
class yap4r {
|
|
|
|
YAPEngine *yap;
|
|
YAPQuery *q;
|
|
std::vector<YAPTerm> args;
|
|
bool failed;
|
|
|
|
public:
|
|
yap4r();
|
|
bool query(std::string p_name,std::string p_module,Rcpp::GenericVector sexps);
|
|
bool more();
|
|
bool done();
|
|
SEXP peek(int i);
|
|
};
|
|
|
|
yap4r::yap4r() {
|
|
YAPEngineArgs *yargs = new YAPEngineArgs();
|
|
yap = new YAPEngine(yargs);
|
|
};
|
|
|
|
|
|
|
|
|
|
bool yap4r::query(std::string p_name,std::string p_module,Rcpp::GenericVector sexps) {
|
|
|
|
if (q) {
|
|
q->close();
|
|
q = NULL;
|
|
}
|
|
std::vector<Term> args = std::vector<Term>();
|
|
yhandle_t sls = Yap_NewHandles(sexps.length());
|
|
for (int i=0; i<sexps.length();i++) {
|
|
if (!sexp_to_pl(sls+i, sexps[i]))
|
|
return false;
|
|
args.push_back( Yap_GetFromSlot(sls+i) );
|
|
}
|
|
YAPTerm qt = YAPApplTerm(p_name,args);
|
|
q = new YAPQuery(qt);
|
|
return true;
|
|
}
|
|
|
|
|
|
|
|
bool yap4r::more() {
|
|
bool rc = true;
|
|
if (failed)
|
|
return false;
|
|
if (q)
|
|
rc = q->next();
|
|
if (!rc) {
|
|
failed = true;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
|
|
bool yap4r::done() {
|
|
|
|
if (failed)
|
|
return false;
|
|
if (q)
|
|
q->cut();
|
|
q = NULL;
|
|
return true;
|
|
}
|
|
|
|
|
|
SEXP yap4r::peek(int i) {
|
|
if (failed || q==nullptr)
|
|
return R_MissingArg;
|
|
return term_to_sexp(Yap_InitSlot(Yap_XREGS[i]), false);
|
|
}
|
|
|
|
|
|
RCPP_MODULE(mod_yap4r) {
|
|
class_<yap4r>( "yap4r" )
|
|
.constructor("create an object encapsulating a Prolog engine")
|
|
.method( "query", &yap4r::query, "create an active query within the engine")
|
|
.method( "more", &yap4r::more, "ask for an extra solution")
|
|
.method( "done", &yap4r::done, "terminate the query")
|
|
.method( "peek", &yap4r::peek, "load arg[i] into R")
|
|
;
|
|
}
|