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yap-6.3/CXX/yapq.hh
2017-02-20 14:38:00 +00:00

220 lines
6.0 KiB
C++

#ifndef YAPQ_HH
#define YAPQ_HH 1
class YAPPredicate;
/**
Queries and engines
*/
/**
* @brief Queries
*
* interface to a YAP Query;
* uses an SWI-like status info internally.
*/
class YAPQuery : public YAPPredicate
{
bool q_open;
int q_state;
yhandle_t q_g, q_handles;
struct yami *q_p, *q_cp;
sigjmp_buf q_env;
int q_flags;
YAP_dogoalinfo q_h;
YAPQuery *oq;
Term names;
Term goal;
// temporaries
void openQuery();
public:
/// main constructor, uses a predicate and an array of terms
///
/// It is given a YAPPredicate _p_ , and an array of terms that must have at
/// least
/// the same arity as the functor.
YAPQuery(YAPPredicate p, YAPTerm t[]);
/// full constructor,
///
/// It is given a functor, module, and an array of terms that must have at
/// least
/// the same arity as the functor.
YAPQuery(YAPFunctor f, YAPTerm mod, YAPTerm t[]);
/// functor/term constructor,
///
/// It is given a functor, and an array of terms that must have at least
/// the same arity as the functor. Works within the current module.
//YAPQuery(YAPFunctor f, YAPTerm t[]);
/// string constructor without varnames
///
/// It is given a string, calls the parser and obtains a Prolog term that
/// should be a callable
/// goal.
inline YAPQuery(const char *s) : YAPPredicate(s, goal, names)
{
BACKUP_H();
__android_log_print(ANDROID_LOG_INFO, "YAPDroid", "got game %ld",
LOCAL_CurSlot);
if (!ap)
return;
__android_log_print(ANDROID_LOG_INFO, "YAPDroid", "%s", vnames.text());
openQuery();
RECOVER_H();
};
/// string constructor with just an atom
///
/// It is given an atom, and a Prolog term that should be a callable
/// goal, say `main`, `init`, `live`.
inline YAPQuery(YAPAtom g) : YAPPredicate(g)
{
goal = YAPAtomTerm(g).gt();
names = TermNil;
openQuery();
};
/// set flags for query execution, currently only for exception handling
void setFlag(int flag) { q_flags |= flag; }
/// reset flags for query execution, currently only for exception handling
void resetFlag(int flag) { q_flags &= ~flag; }
/// first query
///
/// actually implemented by calling the next();
inline bool first() { return next(); }
/// ask for the next solution of the current query
/// same call for every solution
bool next();
/// does this query have open choice-points?
/// or is it deterministic?
bool deterministic();
/// represent the top-goal
const char *text();
/// remove alternatives in the current search space, and finish the current
/// query
/// finish the current query: undo all bindings.
void close();
/// query variables.
void cut();
Term namedVars();
/// query variables, but copied out
Term namedVarsCopy();
/// convert a ref to a binding.
YAPTerm getTerm(yhandle_t t);
/// simple YAP Query;
/// just calls YAP and reports success or failure, Useful when we just
/// want things done, eg YAPCommand("load_files(library(lists), )")
inline bool command()
{
bool rc = next();
close();
return rc;
};
};
// Java support
/// This class implements a callback Prolog-side. It will be inherited by the
/// Java or Python
/// class that actually implements the callback.
class YAPCallback
{
public:
virtual ~YAPCallback() {}
virtual void run() { LOG("callback"); }
virtual void run(char *s) {}
};
/**
* @brief YAP Engine: takes care of the execution environment
where we can go executing goals.
*
*
*/
class YAPEngine
{
private:
YAPCallback *_callback;
YAP_init_args init_args;
YAPError yerror;
void doInit(YAP_file_type_t BootMode);
YAP_dogoalinfo q;
public:
/// construct a new engine; may use a variable number of arguments
YAPEngine(
char *savedState = (char *)NULL, char *bootFile = (char *)NULL,
size_t stackSize = 0, size_t trailSize = 0, size_t maxStackSize = 0,
size_t maxTrailSize = 0, char *libDir = (char *)NULL,
char *goal = (char *)NULL, char *topLevel = (char *)NULL,
bool script = FALSE, bool fastBoot = FALSE,
bool embedded = true,
YAPCallback *callback = (YAPCallback *)
NULL); /// construct a new engine, including aaccess to callbacks
/// construct a new engine using argc/argv list of arguments
YAPEngine(int argc, char *argv[],
YAPCallback *callback = (YAPCallback *)NULL);
/// kill engine
~YAPEngine() { delYAPCallback(); }
/// remove current callback
void delYAPCallback() { _callback = 0; }
/// set a new callback
void setYAPCallback(YAPCallback *cb)
{
delYAPCallback();
_callback = cb;
}
/// execute the callback.
////void run() { if (_callback) _callback->run(); }
/// execute the callback with a text argument.
void run(char *s)
{
if (_callback)
_callback->run(s);
}
/// stop yap
void close() { Yap_exit(0); }
/// execute the callback with a text argument.
bool hasError() { return LOCAL_Error_TYPE != YAP_NO_ERROR; }
/// build a query on the engine
YAPQuery *query(const char *s) { return new YAPQuery(s); };
/// current module for the engine
YAPModule currentModule() { return YAPModule(); }
/// given a handle, fetch a term from the engine
inline YAPTerm getTerm(yhandle_t h) { return YAPTerm(h); }
/// current directory for the engine
bool call(YAPPredicate ap, YAPTerm ts[]);
/// current directory for the engine
bool goalt(YAPTerm Yt) { return Yt.term(); };
/// current directory for the engine
bool mgoal(Term t, Term tmod);
/// current directory for the engine
bool goal(Term t)
{
return mgoal(t, CurrentModule);
}
/// reset Prolog state
void reSet();
/// release: assune that there are no stack pointers, just release memory
// for last execution
void release();
const char *currentDir()
{
char dir[1024];
std::string s = Yap_getcwd(dir, 1024 - 1);
return s.c_str();
};
/// report YAP version as a string
const char *version()
{
std::string s = Yap_version();
return s.c_str();
};
Term fun(Term t);
};
#endif /* YAPQ_HH */